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BISMARCK
2007-Oct-22, 04:25 PM
Here's a quote from NASA chief Michael Griffin:




...the goal isn't just scientific exploration... it's also about extending the range of human habitat out from Earth into the solar system as we go forward in time. . . . In the long run a single-planet species will not survive... If we humans want to survive for hundreds of thousands or millions of years, we must ultimately populate other planets. Now, today the technology is such that this is barely conceivable. We're in the infancy of it... I'm talking about that one day, I don't know when that day is, but there will be more human beings who live off the Earth than on it. We may well have people living on the moon. We may have people living on the moons of Jupiter and other planets. We may have people making habitats on asteroids... I know that humans will colonize the solar system and one day go beyond.




I was thinking about it, and as neat as this sounds and whatnot, why does anyone think this is possible? I'm not speaking about the scientific or engineering possibility of it. I'm talking about the psychological possibility of living on a moon around Jupiter, or other bizarre bodies.

I suppose my point is, human beings are animals that have unfathomable millions of years invested into their evolving to be fit for a certain type of environment, which is of course Earth. By and large, the bulk of our species lives in somewhat temperate climates that don't impose too many extremes on our bodies. There are obviously exceptions, like tiny teams of people living on Antarctica or in the middle of the Sahara, but for the most part these anomalies are not actual settled societies, but are instead transient groups. Most of the people on the planet live in places that are mild enough to not require special clothes for a large portion of the year.

So, thanks to technology, we are able to take our prehistoric simian bodies to places that have pretty much no similarity whatsoever to any environments on Earth. The surfaces of Europa or Titan or even Mars are not like any place on this planet, other than that they are cold. Although, they're stupefyingly cold compared even to Antarctica.

Looking beyond the immediately physiological differences that would come up, like lower gravity, temperature extremes, etc etc, that would require highly controlled living environments, there are other more subtle differences like the length of the day, lack of seasons, dimmer sunlight, and that kind of thing.

Living on Europa would be next to impossible to imagine. Its "day" is about 84 hours long, and the sunlight would be quite a bit dimmer out there since Jupiter is much further away from the Sun. But we've evolved to live with a roughly 24-hour cycle with a bright, glaring Sun. What would happen to a human being living there for years or maybe the rest of their life (since that's what true colonization is)? Is it possible for that to be psychologically dealt with?

Anyway, you get my point. What do you think?

Noclevername
2007-Oct-22, 04:41 PM
Humans are extremely adaptable. Experiments have proven that certain variations in length of day/night cycle, oxygen level, humidity, lighting, motion, and other conditions we're used to can be compensated for.

On a large rotating space habitat such as an O'Neill Cylinder, living conditions may be very similar to those on Earth, aside from the overhead view and slight differences in balance perception due to the rotational pseudo-gravity.

The surfaces of moons and small planets may turn out to be unsuitable for colonization due to low gravity, but that hardly means we cannot live in space. If we can't find new lands, we'll build our own out of whatever asteroids are nearby.

Swift
2007-Oct-22, 05:28 PM
Is it possible for that to be psychologically dealt with?

I don't see an intrinsic reason why not. As Noclevername said, humans are extremely adaptable. There are people who live routinely in the Arctic, with 24 hours of day or night depending upon the season, and have done so for thousands of years. The US has kept a year round base at the South Pole for decades. Submarine crews routinely spend 6 months completely underwater.

I suspect that there will be issues and, particularly when you are talking about permanent habitations, these issues might be pretty big, but I don't think they are any bigger than the technical issues. At worst, you might have to raise children so that they are adapted to such an environment before you actually sent them out there to colonize it, though I doubt we would have to go that far.

danscope
2007-Oct-22, 05:57 PM
Here's a quote from NASA chief Michael Griffin:







I was thinking about it, and as neat as this sounds and whatnot, why does anyone think this is possible? I'm not speaking about the scientific or engineering possibility of it. I'm talking about the psychological possibility of living on a moon around Jupiter, or other bizarre bodies.

I suppose my point is, human beings are animals that have unfathomable millions of years invested into their evolving to be fit for a certain type of environment, which is of course Earth. By and large, the bulk of our species lives in somewhat temperate climates that don't impose too many extremes on our bodies. There are obviously exceptions, like tiny teams of people living on Antarctica or in the middle of the Sahara, but for the most part these anomalies are not actual settled societies, but are instead transient groups. Most of the people on the planet live in places that are mild enough to not require special clothes for a large portion of the year.

So, thanks to technology, we are able to take our prehistoric simian bodies to places that have pretty much no similarity whatsoever to any environments on Earth. The surfaces of Europa or Titan or even Mars are not like any place on this planet, other than that they are cold. Although, they're stupefyingly cold compared even to Antarctica.

Looking beyond the immediately physiological differences that would come up, like lower gravity, temperature extremes, etc etc, that would require highly controlled living environments, there are other more subtle differences like the length of the day, lack of seasons, dimmer sunlight, and that kind of thing.

Living on Europa would be next to impossible to imagine. Its "day" is about 84 hours long, and the sunlight would be quite a bit dimmer out there since Jupiter is much further away from the Sun. But we've evolved to live with a roughly 24-hour cycle with a bright, glaring Sun. What would happen to a human being living there for years or maybe the rest of their life (since that's what true colonization is)? Is it possible for that to be psychologically dealt with?

Anyway, you get my point. What do you think?

Hi, It doesn't take long to miss Earth. In a short time, the mind rejects any
former promise to abide by a decision to leave it's treasures for the
maniaical coldness and barren loneliness of space unless there is the absolute, certain reality that one is going home in a while. This concept will not be
subdued, but will erupt in time.
Best regards, Dan

Noclevername
2007-Oct-22, 06:35 PM
Hi, It doesn't take long to miss Earth. In a short time, the mind rejects any
former promise to abide by a decision to leave it's treasures for the
maniaical coldness and barren loneliness of space unless there is the absolute, certain reality that one is going home in a while. This concept will not be
subdued, but will erupt in time.
Best regards, Dan

You're projecting. Many people may feel differently about it than you. And, of course, to the children who grow up there, it will be home, and planet-dwellers will be the "weird" ones.

IsaacKuo
2007-Oct-22, 06:53 PM
Besides, a space habitat would neither be cold nor lonely. Under incessant solar photon bombardment, it's actually keeping cool which is the problem. And since every square foot of real estate will be precious, people will be packed in as tightly as a modern metropolis.

Someone might go nuts from the crowds, perhaps.

Trakar
2007-Oct-22, 07:26 PM
I was thinking about it, and as neat as this sounds and whatnot, why does anyone think this is possible? I'm not speaking about the scientific or engineering possibility of it. I'm talking about the psychological possibility of living on a moon around Jupiter, or other bizarre bodies.

I suppose my point is, human beings are animals that have unfathomable millions of years invested into their evolving to be fit for a certain type of environment, which is of course Earth. By and large, the bulk of our species lives in somewhat temperate climates that don't impose too many extremes on our bodies. There are obviously exceptions, like tiny teams of people living on Antarctica or in the middle of the Sahara, but for the most part these anomalies are not actual settled societies, but are instead transient groups. Most of the people on the planet live in places that are mild enough to not require special clothes for a large portion of the year.

So, thanks to technology, we are able to take our prehistoric simian bodies to places that have pretty much no similarity whatsoever to any environments on Earth. The surfaces of Europa or Titan or even Mars are not like any place on this planet, other than that they are cold. Although, they're stupefyingly cold compared even to Antarctica.

Looking beyond the immediately physiological differences that would come up, like lower gravity, temperature extremes, etc etc, that would require highly controlled living environments, there are other more subtle differences like the length of the day, lack of seasons, dimmer sunlight, and that kind of thing.

Living on Europa would be next to impossible to imagine. Its "day" is about 84 hours long, and the sunlight would be quite a bit dimmer out there since Jupiter is much further away from the Sun. But we've evolved to live with a roughly 24-hour cycle with a bright, glaring Sun. What would happen to a human being living there for years or maybe the rest of their life (since that's what true colonization is)? Is it possible for that to be psychologically dealt with?

Anyway, you get my point. What do you think?

Life in a space colony (particularly what, IMO, is the only truly viable form of space colony - namely an O'neill type orbital colony) would not be psychologically any different from living in any modern human metropolis or urban/suburban environment. Unless you can propose some specific reason or mechanism why this would be dramatically different in its impact upon the Human psyche, I see no reason to consider this a serious problem.

Noclevername
2007-Oct-22, 07:32 PM
And since every square foot of real estate will be precious, people will be packed in as tightly as a modern metropolis.

Someone might go nuts from the crowds, perhaps.

The early space habs might have this problem, although I don't doubt that there will be practical limits to how many can be crammed onto a single hab- only so much life support to go around. As the infrastructure to manufacture such structures grows, in time the ability to support colonists may increase to the point where any excess ETH* population can (relatively) easily and cheaply aquire new habitats.


*Extra-Terrestrial humans.

antoniseb
2007-Oct-22, 07:34 PM
Living on Europa would be next to impossible to imagine. ...Is it possible for that to be psychologically dealt with?
...What do you think?

I think that living in space colonies will be a lot like living in a giant underground shopping mall, or perhaps like living in downtown Minneapolis in the winter. There is no need to go outside, and inside has been made pretty nice to be in and quite airy.

Until such habitats are constructed and safe, you won't be seeing the majority of the human race living off the Earth. Griffin wasn't talking about a time in this century.

BTW, several people have pointed out in other threads that there will never be a mass migration off of the Earth. The increase in off-world population will be through off-world births from a modest number of colonists.

Noclevername
2007-Oct-22, 07:47 PM
BTW, several people have pointed out in other threads that there will never be a mass migration off of the Earth. The increase in off-world population will be through off-world births from a modest number of colonists.

Exactly. There are no limits to growth in space. (population-wise, or economic.)

BISMARCK
2007-Oct-22, 08:10 PM
I think that living in space colonies will be a lot like living in a giant underground shopping mall, or perhaps like living in downtown Minneapolis in the winter. There is no need to go outside, and inside has been made pretty nice to be in and quite airy.

Until such habitats are constructed and safe, you won't be seeing the majority of the human race living off the Earth. Griffin wasn't talking about a time in this century.

BTW, several people have pointed out in other threads that there will never be a mass migration off of the Earth. The increase in off-world population will be through off-world births from a modest number of colonists.


Ok, but the difference is that you never leave the underground mall. That's what differentiates space colonization from space exploration. The people that live on these colonies are there for life, just like the colonists that came to North and South America. They came here to settle and had no illusions about going back to Europe.

So, I'd say living in the floating equivalent of a gigantic underground mall for the rest of your life is most likely psychologically untenable, based on my experience anyway.

Noclevername
2007-Oct-22, 08:18 PM
So, I'd say living in the floating equivalent of a gigantic underground mall for the rest of your life is most likely psychologically untenable, based on my experience anyway.

Human beings are adaptable. The ones who like the conditions will stay, the rest will give up and move back home (No refunds!). As larger and more airy and open habitats with more realistic parks and gardens are built, it will become less of a problem.

antoniseb
2007-Oct-22, 08:20 PM
So, I'd say living in the floating equivalent of a gigantic underground mall for the rest of your life is most likely psychologically untenable, based on my experience anyway.

If there were a million people living in an underground colony on Callisto, they would probably need more than a thousand square miles of livable colony space, which presumably would have many stadium or larger sized rooms/parks. This is especially true if they were using botanical methods to create food, and convert carbon dioxide into food and oxygen.

IsaacKuo
2007-Oct-22, 08:28 PM
So, I'd say living in the floating equivalent of a gigantic underground mall for the rest of your life is most likely psychologically untenable, based on my experience anyway.

God, I'd love that. It wouldn't even need to be all that gigantic. I've experienced the "wide" outdoors. It does nothing for me, that I couldn't get from a view of open outer space unfettered by clouds or light pollution. And while living 24/7 in zero gee might be bad for one's health, relaxing in zero gee lounges and participating in zero gee sports is something you won't get on Earth.

Noclevername
2007-Oct-22, 08:35 PM
And while living 24/7 in zero gee might be bad for one's health, relaxing in zero gee lounges and participating in zero gee sports is something you won't get on Earth.

And all you'd need to do to reach it from your home is take an elevator up. :)

galacsi
2007-Oct-22, 08:52 PM
A very important point IMO : To succeed the space colonies must be open societies where anybody can have his say and eventually vote with his feet and go away.AKA they must not be directed by corporations or a religious leader. And be populated by free associated people with their own means of living.

If this is not the case very rapidly they will evolve in mini dictatorial states and the colonists trapped inside will not find heaven but hell in the sky.In fact they will be slaves living in some forgotten rat holes of the universe.

And these colonies will collapse from the inside with riots , revolutions , mass emigration or mass suicides.

Ilya
2007-Oct-22, 09:01 PM
A very important point IMO : To succeed the space colonies must be open societies where anybody can have his say and eventually vote with his feet and go away.AKA they must not be directed by corporations or a religious leader. And be populated by free associated people with their own means of living.

If this is not the case very rapidly they will evolve in mini dictatorial states and the colonists trapped inside will not find heaven but hell in the sky.In fact they will be slaves living in some forgotten rat holes of the universe.


Very good point, and one I first saw made in "Wizard" by John Varley, published in early 80's. In his world, some of orbital habitats had the most repressive societies in human history -- and many died through sheer incompetence, augmented by religious self-importance. The only habitat detailed at length was not especially repressive, but was among the most isolationist -- a lesbian separatist one. By the time of the story, none of the inhabitants knew the word "lesbian", because they were unaware of any alternative.

Swift
2007-Oct-22, 09:16 PM
Human beings are adaptable. The ones who like the conditions will stay, the rest will give up and move back home (No refunds!). As larger and more airy and open habitats with more realistic parks and gardens are built, it will become less of a problem.
John Varley, in many of his science fiction novels and short stories, describes a rather large society on the moon (multiple millions of people in several cities). They develop what they call disneys (small d, no copyright infringement ;) ). These are large volumes underground in the moon, 10s of kilometers in diameter. IIRC, the early ones were natural "bubbles", later ones were hollowed out by nuclear explosions. They fill them with various ecosystems (IIRC, one was "Kenya", one was "Kansas", I think there were others). In one of his short stories, the main character creates a new art form, controlled weather events in these closed systems (like Blizzard and Twister) as entertainment.

He also touches on many of the changes in this lunar society, because of the "living in a mall" environment. For one thing, since there are no temperatures extremes, clothing becomes very optional. However, things like body oder and other anti-social behaviors, become crimes.

Again, I see no intrinsic reason that people can't get used to this life. As someone pointed out, it might not work for everyone; there are people who can't imagine living in a big city like New York or London, and there are people who can't imagine living anywhere else. The same hold trues for living on a 1000 square mile ranch where your nearest neighbors are a two hour drive away.

Noclevername
2007-Oct-22, 09:58 PM
There will be room for almost anything. If a colony wants to emulate the Klingon lifestyle right down to the customs and language, they can. And their descendants will not much care that their founders were basing their values on a fictional franchise, to them it'll just be Tradition. If someone wants to build a reinforced high-gravity habitat, and live there just to see what it's like, only the laws of physics and what they can afford will constrain them.

Warren Platts
2007-Oct-23, 01:52 AM
Living on Europa would be next to impossible to imagine. Its "day" is about 84 hours long, and the sunlight would be quite a bit dimmer out there since Jupiter is much further away from the Sun. But we've evolved to live with a roughly 24-hour cycle with a bright, glaring Sun. What would happen to a human being living there for years or maybe the rest of their life (since that's what true colonization is)? Is it possible for that to be psychologically dealt with?

Anyway, you get my point. What do you think?

The Galilean satellites are radioactive hells. On the other hand, Almathea and Thebes might be nice places. . . . :D

The view would be spectacular at any rate. :boohoo:

danscope
2007-Oct-23, 02:52 AM
You're projecting. Many people may feel differently about it than you. And, of course, to the children who grow up there, it will be home, and planet-dwellers will be the "weird" ones.

I would suggest that you go sign on to the crew of a nuclear submarine,
without leave for ten years. Let me know how you feel by Easter.
Let me know how you long for the holidays.
Shall I tell you how you will miss the seasons? Or...genuine society?
There is a small difference between the hot tub philosopher and
Robinson Crusoe. Walk around his island for a while and truly ponder that situation. Then I will ponder your praise for the vaccuum of space.
Besr regards, Dan

Noclevername
2007-Oct-23, 03:05 AM
I would suggest that you go sign on to the crew of a nuclear submarine,
without leave for ten years. Let me know how you feel by Easter.
Let me know how you long for the holidays.
Shall I tell you how you will miss the seasons? Or...genuine society?
There is a small difference between the hot tub philosopher and
Robinson Crusoe. Walk around his island for a while and truly ponder that situation. Then I will ponder your praise for the vaccuum of space.
Besr regards, Dan

Absolute nonsense. People are not going to design permanent habitats that are anything like submarines*. Just because you wouldn't go doesn't mean no one would. As for "genuine society", the majority of people lived in isolated small villages for many millenia. They didn't have radio, TV or internet contact, as colonists will. And somehow they got along just fine without "genuine" society. Many present day people live in places where there is no seasonal change. As I said above, you are projecting your feelings onto others. There are other points of view, needs and desires.


* Or to put it another way, if it's designed like a submarine, no one's going to use it as a permanent habitat.

danscope
2007-Oct-23, 05:11 AM
We would be lucky if we had the advantages of a submarine..including unlimited water, cooling, radiation shielding in the form of sea water, and a medium in which to turn a propeller for thrust. Even the ability to harvest fish and seaweed
would be welcome . In space, these luxuries are not present.
To study structures as pressure vessels is revealing. Like a boiler, even the one in your home, must endure the pressure of 15 pounds per square inch. They go through a lot of trouble to sustain just this....over a small area. Larger structures and pressures are strain on the scientific disciplines. Take a look at a 1200 pound steam boiler...yea 1800 lb. boiler. Now...an aircraft fuselage which is pressurized ,is such a vessel. It is light, strong, and tubular which by design will sustain uniform pressure from within . There are limits
owing to interior corrosion and cyclical pressure deterioration(although as a space station module, this should not apply. But if I were to want to select a material for long term design pressure vessels in space at one atmosphere,
I should want monel. But that is a luxury in weight and expense. It is durable however. Unlike Skylab which was simply discarded for what ever reason,
we should.must needs, build something more durable, more usefull and
quite simply.....Safe. This would be a noble purpose and worthy of construction, especially if it were in a usefull orbit ie serviceing of
space telescopes etc. There we have a worthy purpose in space.
We are going to have increasingly more trouble keeping such a space station
clean enough that it doesn't become a bio-hazard. They'll be writing books about this one.
A colony? I should think not. Not with what we know today.
It will be an island in the sky, visited for scientific purpose. I believe this to be the fact of the matter.

When you have studied and begin to realize the practical engineering considerations of building a space habitat, you will abandon the concept of
maga structures in space. There are serious limitations beyond your knowledge.
I appreciate your enthusiasm.
Just out of curiousity, have you ever been to sea.....for a substantial period of time?
Best regards, Dan

IsaacKuo
2007-Oct-23, 02:29 PM
We would be lucky if we had the advantages of a submarine..including unlimited water, cooling, radiation shielding in the form of sea water, and a medium in which to turn a propeller for thrust.

This comparison to military submarines is utterly ludicrous. First off, a submarine has to deal with much HARSHER conditions than an orbital habitat. The hull of a submarine must deal with dozens of atmospheres of pressure. An orbital habitat has to deal with only one atmosphere of pressure. A submarine is immersed in frigid water that is constantly sapping away heat. Even an Antarctic base has an easier time staying warm. An orbital habitat is surrounded by an insulating vacuum.

A military submarine needs to move in order to perform its mission. That means it needs to be streamlined and all excess volume is eliminated. Furthermore, it needs to sink in order to perform its mission. No military submarine will ever have any large open spaces outside the ballast tanks because that literally means weighing down the sub with the equivalent mass of water.

In contrast, look at a cruise ship. A cruise ship isn't designed for a military mission, and it's not designed to sink. Cruise ships have large open spaces.


Even the ability to harvest fish and seaweed
would be welcome.

That's what hydroponics are for.


To study structures as pressure vessels is revealing. Like a boiler, even the one in your home, must endure the pressure of 15 pounds per square inch. They go through a lot of trouble to sustain just this....over a small area. Larger structures and pressures are strain on the scientific disciplines.

No, they aren't. O'Neill already did engineering calculations using plain old steel and glass, and found to his surprise that the pressures were quite manageable even for very large habitats. The real limitation is radiation shielding. If you've got the 2 meters of steel to keep out the radiation, it'll easily keep in the air.

Trakar
2007-Oct-23, 03:06 PM
No, they aren't. O'Neill already did engineering calculations using plain old steel and glass, and found to his surprise that the pressures were quite manageable even for very large habitats. The real limitation is radiation shielding. If you've got the 2 meters of steel to keep out the radiation, it'll easily keep in the air.

Mass shielding will more probably come in the form of fused silica regoliths, but your point is the same. Personally, I'd expect initial habs to be most similar to the Stanford torus designs, and not sure that the large, closed end, hollow cylinder, O'neill designs would ever be truly practical or even desirous (beyond the spectacular views aspect). But these aren't issues of psychology or physiology.

galacsi
2007-Oct-23, 08:32 PM
Hi

I am very curious to know how you , habitat enthusiasts , see the construction of any of these mega structures ?

Practically , with which materials ? , how to obtain , manufacture and transport the materials ? How to assemble the parts ? How to finance ? how to recover your money ? Make a profit ?

How long an habitat can last ? What about metal fatigue ?
Resonant vibrations ? how to mend a puncture ? What about breakdowns ? And so on . . . .

Warren Platts
2007-Oct-23, 08:38 PM
One thing that strikes me as unrealistic about truly grand designs like O'Neill tubes is there's no way to set "condition zebra" in such a facility. It wouldn't have to take a big meteor to cause a 500 foot gash. It could be something a lot stupider, like a terrorist with a homemade bomb. Such a hole can't be fixed in a day. So, how would you keep the rest of the station pressurized until it does get fixed?

Noclevername
2007-Oct-23, 08:52 PM
One thing that strikes me as unrealistic about truly grand designs like O'Neill tubes is there's no way to set "condition zebra" in such a facility. It wouldn't have to take a big meteor to cause a 500 foot gash. It could be something a lot stupider, like a terrorist with a homemade bomb. Such a hole can't be fixed in a day. So, how would you keep the rest of the station pressurized until it does get fixed?

For something the size of an O'Neill Cylinder, a 500 foot gash is like a pinprick. Fast-response damage control teams with multi-sectional patching plates could be stationed around the hull. You might just as easily ask, "Who'd want to live in a city? With all those buildings so close together, a fire would spread and wipe everyone out!"

IsaacKuo
2007-Oct-23, 08:55 PM
One thing that strikes me as unrealistic about truly grand designs like O'Neill tubes is there's no way to set "condition zebra" in such a facility. It wouldn't have to take a big meteor to cause a 500 foot gash. It could be something a lot stupider, like a terrorist with a homemade bomb. Such a hole can't be fixed in a day. So, how would you keep the rest of the station pressurized until it does get fixed?

While everyone is familiar with the grand pictures of forests and lakes, the innermost floor actually only provides a fraction of the potential living space. Underneath the picturesque "natural" looking park can be many floors of compartmentalized living areas.

Obviously, the people in the immediate area of the bomb/impact are screwed no matter what. But the people in the rest of the habitat can evacuate the innermost floor to the compartmentalized floors. The innermost floor is like the equivalent of beachfront property. It's expensive and nice, but don't be too shocked if it gets battered by a hurricane or tsunami.

Noclevername
2007-Oct-23, 08:59 PM
It wouldn't have to take a big meteor to cause a 500 foot gash. Obviously if you're going to park a large colony in a particular orbit, you will first check to make sure there are no 500 meter asteroids crossing it. Prior Planning Prevents Poor Performance.


When you have studied and begin to realize the practical engineering considerations of building a space habitat, you will abandon the concept of
maga structures in space. There are serious limitations beyond your knowledge.
Your attitude and assumptions are not appropriate. I have spent my entire life studying the concept. I know a great deal about the exact difficulties and complexities involved. I also know that none of them are insurmountable. You seem to think that no one has ever thought about these problems. I assure you that many individuals with a great deal of expertise have been and are examining more aspects of space colonization than you or I have ever thought of. Do not insult my intelligence or knowledge simply because I disagree with you.

IsaacKuo
2007-Oct-23, 09:15 PM
I am very curious to know how you , habitat enthusiasts , see the construction of any of these mega structures ?

Speaking for myself, I see it in the far future, at least two centuries from now (unless really neat-o technology speeds things up a lot).


Practically , with which materials ? , how to obtain , manufacture and transport the materials ? How to assemble the parts ? How to finance ? how to recover your money ? Make a profit ?

I'll start with "Make a profit", because that's the big one. As I see it, there is no product for space colonists to sell back to Earth, other than a very limited demand for space tourism. Therefore, the only product a colony has to sell is living space. How can you make a profit? Only if it's economical for a person or family to buy a home in the space colony as well as pay for whatever extra equipment is required to support them for life (if any such equipment is required).

This requires much more than merely the technological capability to create a habitat. It must be economical, as well as possible. This is the reason why Freedom Ship is utterly retarded. It's certainly possible to make a huge cruise ship that people could live on permanently. But it makes no economic sense.

So, IMO, space habitats will only happen after technology has improved to provide cheap space launch capability. Whether this is laser launch or kinetic impact rocket or whatever, I don't see it within the next century.

Now, given that we're talking about materials science and manufacturing technology at least two hundred years more advanced than our own, the rest of the problems don't look so bad. The material I favor is vapor deposited diamond--a substance which is limited to thin coatings today, but in the vast vacuum of outer space it could be economical. It's stronger and more durable than steel, but it's also transparent. The main structure can consist of concentric cylindrical floors, with pedestrians, bikes, cars, and trains seemingly "walking on air". Buildings would have opaque walls for privacy, of course, leaving the visual effect of skyscrapers with people and transports hovering in the air between them.

The materials would come from NEOs or atmospheric scooping. Venus has a practically unlimited supply of carbon dioxide in the upper atmosphere. This can be split into carbon to form the habitat shells and oxygen for breathable air.

neilzero
2007-Oct-23, 09:47 PM
A 500 centimeter asteroid can make a 500 foot gash, if the speed difference is big enough, but a homemade bomb would not damage the ten meter thick plus outer wall of the cylinder, unless the bomb maker was both skilled and lucky.
At present we know the orbits of less than 1% of the 1 to 5 meter asteroids, but a very costly program can chart 99% of the asteroids over one meter. It may be 1000 years before we chart 99% of the comets with a nucleus over one meter.
I suppose a 500 foot gash can be fixed in minutes with a big enough emergency repair team, but will our repair team remain alert if only one large gash occurs per century? We had 50,000 vehicles barely moving West on I10the last huricane evactuation order. Many ran out of gas, because of the very low speed. Luckily the wind did not gust more than 60 knots on the I10 parking lot, so injuries were few. Neil

Noclevername
2007-Oct-23, 11:22 PM
The first large-scale permanent colonies may very well not exist this century-- although I wouldn't rule it out entirely. But the smaller steps taken to get there will definitely be taking place in this century, and some of it probably in the next few decades. Besides the technology and ecology needed to be developed for the habitats themselves, two basic things will be required; Large-scale, cheap human access to space, and a cheap and easily accessible source of building materials. Both may have to wait until next century-- depending, of course, on how this century goes. The future is not always predictable. We are in the same position today as those science fiction authors in the first years of the 20th century trying to paint a picture of what the next hundred years would be like, and a century from now our concept of the future may look as funny and dated as their ideas do to us.

Swift
2007-Oct-24, 02:51 AM
Obviously if you're going to park a large colony in a particular orbit, you will first check to make sure there are no 500 meter asteroids crossing it. Prior Planning Prevents Poor Performance.

So, you're having your safety audits at work too? ;)

Noclevername
2007-Oct-24, 02:54 AM
So, you're having your safety audits at work too? ;)

No, I just have some friends with poor impulse control.

filrabat
2007-Oct-28, 01:31 AM
Economics/Paying for Itself -

To start with, either one of two things need be true
*A self-sustaining source of food, or near enough to it not to make any difference
*High valued of either that can pay for any importation of food Goods(unlikely, given that raw materials for X good can always be transported to a Earth-based factory much cheaper than to even a LEO, let alone a HEO and especially the Moon or a Planet)
Services(probably a little more likely, but that assumes that people WANT to live for a least several years in space in the first place - itself a non-proven assumption)
Tourism - related to services (this is the most likely one, though it's a flimsy economic base unless you offer something with an impressive "Wow" factor that'd impress even Hollywood, Las Vegas, Rio-at-Carnival, or Paris [low-G can't really be replicated on earth, so that offers some home])

Personally, I think tourism combined with self-sustaining food production is likely the best bet. Otherwise, the only other thing I can think of is an "everything goes" kind of libertine and/or nonjudgmental cultural environment -- kind of like Amsterdam in orbit. Regardless, I don't see how orbitals can be sustainable in the long run unless you can produce at least slight food and water and O2 surpluses on demand.

danscope
2007-Oct-28, 04:41 PM
Hi, I think that is the accurate assesment of the situation. And frankly,
I don't see and bottom line in black ink for a space station. There is no potential
product or service that can provide even a small income that can pay a
very small percentage of the cost to construct, boost , man , and maintain
a space station . It, like a boat, will be a hole into which nations shall pour money in large quantities . No question .
Best regards, Dan

filrabat
2007-Oct-28, 06:33 PM
Dan,

IMO, that depends ultimately on self sufficiency in food, water, nutrients, and oxygen. Self sufficiency in those elements, combined with rigorous population controls, can really take a bite from the long term costs (the initial outlay may be out of the wazoo, but given a high valued service or creative endeavor with a basic low-material requirement, it might succeed).

I know several here will disagree with my layout, but this is how I see it.

I don't know if hydrophonics alone can generate enough food to sustain a small population (around 10) indefinitely, but if not, then gradually importing soil from earth into at least part of a habitat is a bare-bones basic start. I prefer to use "natural" approaches as much as possible because they require less complex machinery to operate - particularly regarding oxygen generation.

Basically, import high O2 generating grasses along with the soil, plus some microorganisms known to decompose grass. Put these in a sealed chamber, and you have a great O2 source. Then add some more (how ever gradually) until you have enough to support at least a few people indefinitely. I'll admit you'll have to do at least fairly intensive hydroponics at first to supply food, but this system at least can have some degree of self-sustainability.

Noclevername
2007-Oct-28, 07:05 PM
I'll admit you'll have to do at least fairly intensive hydroponics at first to supply food, but this system at least can have some degree of self-sustainability.

But in a small, closed system, soil may not be self-sustainable.

Trakar
2007-Oct-28, 07:28 PM
But in a small, closed system, soil may not be self-sustainable.

Aeroponics systems tend to be more efficient and don't require soil of any form.

Noclevername
2007-Oct-28, 07:43 PM
Soil is full of random organisms that may make a mess of a planned ecology. Not to mention that at least some of that soil will eventually wind up in the mechanisms that are needed to sustain all the other functions of the habitat.

filrabat
2007-Oct-28, 08:58 PM
I guess there's little, if any, way around the techno-intensive solution to biological self-sustaination in the short term. When starting out, aeroponics (or hydroponics, if possible) would be the way to go. (My mind keeps jumping between early and "maturing" stages of habitat construction)

As for soil winding up in the mechanisms needed to sustain functions: Assuming a "1G or close to" pseudo-gravity, couldn't we just isolate the plants in a separate cell, to keep the soil from messing with the machinery? (I'm picturing essentially a well sealed greenhouse, with an air pipe at the "top" of the house...with only a few small fans to circulate the air throughout the habitat). In short, a plant (read: O2 generating) area, and a human-machine area.

Noclevername
2007-Oct-28, 09:20 PM
I guess there's little, if any, way around the techno-intensive solution to biological self-sustaination in the short term. When starting out, aeroponics (or hydroponics, if possible) would be the way to go. (My mind keeps jumping between early and "maturing" stages of habitat construction)

As for soil winding up in the mechanisms needed to sustain functions: Assuming a "1G or close to" pseudo-gravity, couldn't we just isolate the plants in a separate cell, to keep the soil from messing with the machinery? (I'm picturing essentially a well sealed greenhouse, with an air pipe at the "top" of the house...with only a few small fans to circulate the air throughout the habitat). In short, a plant (read: O2 generating) area, and a human-machine area.

Unless you posit a separate maintainance crew living in the farming section, human access will be necessary. It would not be possible given any near-term technology to prevent some soil particles from migrating.

danscope
2007-Oct-29, 05:37 AM
We do it every day. Iy's called clean room conditions. You pass through a port
when entering and leaving an area. This is not invention, but standard procedure. Yes the system demands respect. That's why we employ brainy people in space.
And speaking of great people, How about those Red Sox!!!!
Best regards, Dan :)

Noclevername
2007-Oct-29, 05:45 AM
We do it every day. Iy's called clean room conditions. You pass through a port
when entering and leaving an area. This is not invention, but standard procedure.

Yes, but they aren't full of dirt. Hence the term "clean".

ADDED: Cleanrooms also normally do not provide all the air and food for a small enclosed space where all materials must be recirculated, or contain working greenhouses.

IsaacKuo
2007-Oct-29, 02:25 PM
Aeroponics and hydroponics are more or less the same thing, just with a different amount of water used. I favor hydroponics because currently it seems to be more efficient and more mature, and I figure any reasonable habitat will have a decent amount of water.

In particular, I think any reasonable habitat is going to at least have a large store of emergency water, along with a decent amount of emergency dried food. The latter needs water, of course.

Noclevername
2007-Oct-29, 03:25 PM
In particular, I think any reasonable habitat is going to at least have a large store of emergency water, along with a decent amount of emergency dried food. The latter needs water, of course.

And water can also help provide additional radiation shielding.

danscope
2007-Oct-29, 03:55 PM
Hi,
I think the fly in the ointment is going to be mold. Dealing with this problem is going to be extraordinary. And you can't hose the place down with bleach and just open the windows for a fresh change of air. This is a tough one.
Best regards, Dan

Noclevername
2007-Oct-29, 03:59 PM
Dealing with this problem is going to be extraordinary.

No more so than any other aspect of a small closed ecosystem.

filrabat
2007-Oct-29, 07:36 PM
Economic Sustainability (again)

This post treats realistic degrees of food/O2/H2O sustainability, plus rapid capacity increase capability as a "black box" and just assumes that somehow, some way, we solved the problem.

What kinds of service industries are high-valued enough to create economically sustainable habitats (Assume a 1G rotation or close to it)?

What is there in a habitat that could make people want to live there? I came up with unique experiences, a more libertine social environment (potentially), possibly bragging rights to "living with a cool view of the earth". Possibly it could be a place for people with hampered mobility (physically challenged, aged people with weak bones).

A lot, of course, depends on what the G is in the first place (for obvious reasons, low G applies most to the last groups mentioned). Perhaps slightly higher G environments would appeal to people who are young, full of physical vigor, and like to stay in shape (1.1 to 1.25 G environments seem a great way to burn off extra calories and give a good continuous workout to the muscles as long as you don't spend too much time in the higher G's -- potential back problems, you know).

Seems to me like techies, etc would disproportionately be represented in that group, for the novelty sake, if nothing else. Then, there'd be the maintainence crews, representatives of financial companies, etc. to serve the techies and other science types in orbit (seeing an opportunity for "space duty pay").

Doodler
2007-Oct-29, 09:12 PM
The Galilean satellites are radioactive hells. On the other hand, Almathea and Thebes might be nice places. . . . :D

The view would be spectacular at any rate. :boohoo:

Only Io and Europa are untenably radioactive.

filrabat
2007-Oct-29, 09:15 PM
One good thing about a literal designer ecosystem....the ecosystem literally CAN revolve around us (well, much closeER, at least).

Still, no matter what happens, there's still the danger of different strains of the same microbe species evolving to become less or more deadly in the habitat than on earth. That's going to be a challenge as well. For kids born up there especially, immunology's going to be quite challenging (not just microbe resistance, but asthma, pollen, etc). Seems like frequent immunization's going to be fairly routine for a few centuries (or whenever we develop habitats with populations of small nations WITH frequent travel between earth/other habitats and that habitat - sort of like Iceland, or island tourist destinations)

Noclevername
2007-Oct-30, 12:24 AM
What kinds of service industries are high-valued enough to create economically sustainable habitats (Assume a 1G rotation or close to it).

What is the definition of economically sustainable for a self-sufficient habitat?

I'd say, with essentially unlimited energy, near-term recycling and manufacturing technologies and a closed-loop ecosystem, a finished habitat that is not taking in any more population will only need new materials to replace what is lost to airlock use and leaks, barring emergency. How much that would be will depend on the efficiency of their design and ecology.

Trakar
2007-Oct-30, 04:38 PM
Aeroponics and hydroponics are more or less the same thing, just with a different amount of water used. I favor hydroponics because currently it seems to be more efficient and more mature, and I figure any reasonable habitat will have a decent amount of water..

Not at all, aeroponics is fully mature and much more efficient, additionally the plants produce better in aeroponic systems. And water requirements are a serious and major concern, especially for initial small habitats.

http://www.biocontrols.com/aero122.htm


http://www.techbriefs.com/content/view/1294/118/


http://sbir.nasa.gov/SBIR/successes/ss/10-026text.html

Noclevername
2007-Oct-30, 05:08 PM
At first, enforced population controls will be needed. As our space-based capacity for manufacturing habitats and transporting people increases, these restrictions may slowly be lessened and eventually lifted entirely, as excess peopulation* can simply be given their own homes.

*How about that, I invented a new word. Either people or population would work there, pick one and imagine that's what I really typed.

IsaacKuo
2007-Oct-30, 06:35 PM
Not at all, aeroponics is fully mature and much more efficient, additionally the plants produce better in aeroponic systems. And water requirements are a serious and major concern, especially for initial small habitats.

Hydroponics is still more mature than aeroponics, and I'm not convinced by company PR. If aeroponics were so much better than hydroponics, why has it only acheived limited commercial success in comparison?

Hmm...now that I think about it, I'm not sure it's even possible to use aeroponics to grow algae. In any case, my hope for hydroponic algae is to minimize logistic support man-hours by simply putting the algae in zero maintenance transparent tubes directly exposed to sunlight. Pumps would keep the fluid circulating to centralized equipment to exchange air and occasionally harvest algae.

The aeroponics systems seem rather labor intensive, with clipping of seedlings and manual placement of plants into fixed holders. In contrast, a vat of pond scum algae requires very little maintenance effort.

Van Rijn
2007-Oct-30, 08:22 PM
What is the definition of economically sustainable for a self-sufficient habitat?

I'd say, with essentially unlimited energy, near-term recycling and manufacturing technologies and a closed-loop ecosystem, a finished habitat that is not taking in any more population will only need new materials to replace what is lost to airlock use and leaks, barring emergency. How much that would be will depend on the efficiency of their design and ecology.

(Emphasis added). Closure is a big problem. It starts to be an significant issue above around 80%, and begins to get seriously tricky at about 90%. The last few percent are the hardest, and starts requiring a lot of mass in the system (in hardware, size of the biological components, etc.) and more maintenance. We need to do a lot more research on this stuff.

Noclevername
2007-Oct-30, 10:08 PM
(Emphasis added). Closure is a big problem. It starts to be an significant issue above around 80%, and begins to get seriously tricky at about 90%. The last few percent are the hardest, and starts requiring a lot of mass in the system (in hardware, size of the biological components, etc.) and more maintenance. We need to do a lot more research on this stuff.

Yes, we definitely do.

Noclevername
2007-Oct-31, 12:20 AM
Getting back to the OP about human psychology in space, colonists will probably need to have a strong sense of responsibility; when your every breath, and that of your family and friends, rely on complex life support systems, no one can afford to be lazy or sloppy. Likely in small habitats a villiage mentality will develop-- strangers will be rare, at least for face-to-face meetings.

Trakar
2007-Oct-31, 06:50 PM
Hydroponics is still more mature than aeroponics, and I'm not convinced by company PR. If aeroponics were so much better than hydroponics, why has it only acheived limited commercial success in comparison?.

Aeroponics was first investigated in 1942 (Carter, W.A. 1942. "A method of growing plants in water vapor to facilitate examination of roots." Phytopathology 732: 623-625). There are multihectacre aeroponic plantations in singapore and malaysia, and small scale home production units across the face of the globe, with hundreds of companies supplying everything from do-it-yourself kits to full-up commercial production systems.


Hmm...now that I think about it, I'm not sure it's even possible to use aeroponics to grow algae. In any case, my hope for hydroponic algae is to minimize logistic support man-hours by simply putting the algae in zero maintenance transparent tubes directly exposed to sunlight. Pumps would keep the fluid circulating to centralized equipment to exchange air and occasionally harvest algae..

Might be good as atmospheric/water regeneration systems, and would provide a base-stock product that could possibly be used as animal feed supplement, but in order to produce anything out of it that would be palatable and appetizing human food it would require extensive processing and preparation.

With aeroponics I get the same atmosphere benefits, and have a large natural variety of fruits and vegetables that I can pluck and eat. They produce faster and in larger volume than hydroponic systems and require a small fraction of water.


The aeroponics systems seem rather labor intensive, with clipping of seedlings and manual placement of plants into fixed holders. In contrast, a vat of pond scum algae requires very little maintenance effort.

Certainly less labor than would be required to turn a vat of pond scum into something I would enjoy eating on a regular basis.

IsaacKuo
2007-Oct-31, 07:04 PM
Well, I like dried nori seaweed. ;)

eburacum45
2007-Oct-31, 07:10 PM
Several types of seaweed are nice to eat; but I wouldn't like to eat them all the time.

Noclevername
2007-Oct-31, 07:19 PM
Even freshwater plants will be complex to maintain, adding sea salt to equation makes it even more so. I think only the largest (later) colonies will be able to maintain oceanic life. Most space dwellers may go their entire lives without seeing (or tasting) sea creatures.

IsaacKuo
2007-Oct-31, 07:25 PM
Any sort of hydroponics or aeroponics will involve water with dissolved nutrient solutions. Salt is just something else you could dissolve into the mix.

Warren Platts
2007-Oct-31, 08:04 PM
Only Io and Europa are untenably radioactive.
What if we used one of those tether systems to deplete Jupiter's Van Allen Belt?

If we can't do that, Ganymede seems like a nice place.


Not at all, aeroponics is fully mature and much more efficient, additionally the plants produce better in aeroponic systems. And water requirements are a serious and major concern, especially for initial small habitats.The problem with aeroponics is that if your power goes out, you've got 20 minutes to fix the problem before all your plants die. With a rockwool system, you've got several hours to a couple of days to fix it.

Really, what's wrong with going organic? It wouldn't be hard to make your own soil by composting organic wastes and combining with the local dirt, and it would be a lot more fail-safe, besides tasting better.

Noclevername
2007-Oct-31, 08:14 PM
Really, what's wrong with going organic? It wouldn't be hard to make your own soil by composting organic wastes and combining with the local dirt, and it would be a lot more fail-safe, besides tasting better.

It's not hard on Earth to do that. But soil (and compost, for that matter) is actually a complex web of organisms, harder to replicate than we once thought. Some form of 'ponics will actually be easier to establish and care for than a soil-based system, even if it seems counterintuitive to us who equate "soil" with "simple".

IsaacKuo
2007-Oct-31, 08:17 PM
One possible problem with soil is that it blocks sunlight. One obvious place to put algae tubes is around the outer floor, with sunlight entering from below. Soil would block sunlight from below.

Warren Platts
2007-Oct-31, 09:29 PM
If you were going to build a colony on the Moon, would you make greenhouses open to the sun? You'd have to have supplemental lighting during the two weeks of night, but it would free up a lot of electricity for other uses during the two weeks of daylight. I figure plants could probably survive most solar eruptions without extra protection.

IsaacKuo
2007-Oct-31, 09:33 PM
Where does the electricity during the two weeks of night come from?

(I don't have a good answer for that one, which is a reason I wouldn't build a colony on the Moon.)

Noclevername
2007-Oct-31, 09:43 PM
Seeds could be stored in a strongly shielded hab section. In case of solar storm, make sure to keep enough spare food and O2 (and filters for CO2) to last until the new replacement crop comes in.

Warren Platts
2007-Oct-31, 09:57 PM
Power for the dark periods is going to have to come from nuclear, for base load. Huge solar arrays could power aluminum smelting and other energy intensive industries during sunny periods. But for the dark periods, there's still going to be a huge demand for electricity. What people should be looking for is U235 rather than He3.

Noclevername
2007-Oct-31, 11:20 PM
Orbitting Solar power collectors could beam energy to the surface.

Van Rijn
2007-Oct-31, 11:26 PM
Where does the electricity during the two weeks of night come from?

(I don't have a good answer for that one, which is a reason I wouldn't build a colony on the Moon.)

Aside from nuclear (which I think is one of the best options), other options are:

- Build near a pole with constant sunshine.

- Use power stored from solar during the "day" using regenerative fuel cells or other schemes.

- "beam" it in (microwave or laser target receiver, SPS at a Lagrange point or other convenient location).

Van Rijn
2007-Oct-31, 11:27 PM
Orbitting Solar power collectors could beam energy to the surface.

Parallel posting strikes again.

Noclevername
2007-Oct-31, 11:28 PM
Parallel posting strikes again.

Great minds think alike, and so do ours.

Warren Platts
2007-Nov-01, 12:06 AM
Orbitting Solar power collectors could beam energy to the surface.
Yeah, but to build that kind of stuff in the first place, you need to get manufacturing facilities going on the Moon.

Noclevername
2007-Nov-01, 12:10 AM
Yeah, but to build that kind of stuff in the first place, you need to get manufacturing facilities going on the Moon.

Or a near-Earth asteroid. Technically it could even be done from Earth, at great expense.

Warren Platts
2007-Nov-01, 12:44 AM
Or a near-Earth asteroid. Technically it could even be done from Earth, at great expense.
Eros would probably be the best candidate. But think about the ∆V: granted one could probably do a high jump on Eros and achieve escape velocity, but to get back to Earth LEO would require more ∆V than launching from the Moon's surface. Also, the Moon is much more geologically diverse, so it will have a wider variety of potential resources. Moreover, Eros is practically weightless. The 1/6 g on the Moon would be much more practical for doing actual manufacturing work in a factory (liquids flow properly, tools are flying everywhere, wheeled machines can get traction, etc.)

Noclevername
2007-Nov-01, 02:09 AM
Eros would probably be the best candidate. But think about the ∆V: granted one could probably do a high jump on Eros and achieve escape velocity, but to get back to Earth LEO would require more ∆V than launching from the Moon's surface. Also, the Moon is much more geologically diverse, so it will have a wider variety of potential resources. Moreover, Eros is practically weightless. The 1/6 g on the Moon would be much more practical for doing actual manufacturing work in a factory (liquids flow properly, tools are flying everywhere, wheeled machines can get traction, etc.)

If the ∆V is so high, then maybe Eros isn't such a good candidate. Pick one a little "closer" to Earth in energy terms (some need less ∆V than a Moon trip). And if you can learn to manufacture in zero-g, you can do so anywhere in the Universe. Gravity-only is much more limiting (not to mention that doing so in Lunar g will require nearly as many alterations of Earthly industrial techniques as doing so in zero-g). A simple centrifuge can provide any settling or separation that gravity can.

EDIT:
tools are flying everywhere Tools don't "fly everywhere" in zero g any more than they "fall everywhere" under gravity.

eburacum45
2007-Nov-01, 02:28 AM
A Lunar Grid would supply the power required at night. It might be worth trying out superconducting cables for this purpose
http://en.wikipedia.org/wiki/Electric_power_transmission#Superconducting_cables
I have seen it suggested that such a cable could double as a liquid hydrogen delivery service; certainly hydrogen would be in demand on the Moon.

Noclevername
2007-Nov-01, 02:40 AM
A Lunar Grid would supply the power required at night. It might be worth trying out superconducting cables for this purpose
http://en.wikipedia.org/wiki/Electric_power_transmission#Superconducting_cables
I have seen it suggested that such a cable could double as a liquid hydrogen delivery service; certainly hydrogen would be in demand on the Moon.

Bulding that would require a lot of Lunar infrastructure. It'll probably have to wait until Lunar industries are well-developed.

Ronald Brak
2007-Nov-01, 07:34 AM
Where does the electricity during the two weeks of night come from?

(I don't have a good answer for that one, which is a reason I wouldn't build a colony on the Moon.)


To expand on Van Rijn's post, power could be beamed from earth which would probably be the cheapest option, or heat exchangers could generate power from the heat difference between the cold lunar surface and warmer subsurfaces temperatures at night and vice versa during the day. I would guess the fuel savings from an equatorial base would be worth forgoing the more constant sunlight at the poles. However the possibility of ice deposits at the poles may make a site there more attractive.

Any chance of ice under the surface from comet strikes near the equator if they were buried deep enough? I know on the Apollo 15 mission they wanted to bury probes several meters deep to measure subsurface temperatures and heat flow, but they had trouble drilling.

Warren Platts
2007-Nov-01, 11:05 AM
If the ∆V is so high, then maybe Eros isn't such a good candidate. Pick one a little "closer" to Earth in energy terms (some need less ∆V than a Moon trip).That's certainly news to me. Can you name names? Also, why think NEO asteroids have any more volatiles than will be found on the Moon, given that the perigees of most such asteroids are closer to the Sun than is the Moon's?


EDIT: Tools don't "fly everywhere" in zero g any more than they "fall everywhere" under gravity.I just saw an astronaut on tv who was asked what are the best clothes to wear in space, and she said clothes with lots of pockets, because things tend to "fly everywhere". How many tools do you think NORAD is tracking that have been lost at the ISS?

ASEI
2007-Nov-01, 11:46 AM
Indeed, a lot of manufacturing processes need gravity. If you don't have gravity, you'll have to substitute in centrifuges, which can get much more complicated. Maybe there are clever ways to "do without" gravity or any sort of handy frame-force, but they'll take time to discover, and might end up being harder to make work.

And about asteroids - the ones that have all the volatiles are either out past Ceres, or only visit the inner system for short periods of time. They are valuable, as the moon doesn't have much in the way of volatiles. But they aren't going to be easy to get to. You have to put yourself almost on a solar escape trajectory to get to a comet coming in from the outer system, and that's a LOT of dv. You have to travel out past mars to get to Ceres or any of the outer system iceballs that have accumulated all the volatiles. Hydrogen runs might take up to a year or two before you can get back to the moon.

What you can get from near earth asteroids, you can also get from the moon with less trouble. The ones that have the interesting stuff aren't near earth.

IsaacKuo
2007-Nov-01, 01:43 PM
The problem with beaming energy down to lunar greenhouses is that it makes more sense to just but the greenhouses in orbit where those solar beaming stations are. Consider the extra hardware and losses involved in converting sunlight to electricity, and then converting that electricity into a beam, and then beaming to the Moon's surface.

As opposed to just putting the greenhouses in orbit and they can just absorb sunlight directly.

It makes more sense to build an orbital habitat than a lunar habitat. If you want to exploit lunar resources, do it with robotic mining equipment that can afford to sit in idle "hibernation" two weeks out of the month.

As for the other ideas:

Nuclear? Really expensive compared to solar, and doesn't scale down well.

Lunar power wires? Even more expensive than beaming energy, and with comparable losses unless you use superconductors.

Polar building? Okay, that's good for two tiny bits of real estate. That could be worth doing, but you're limited to exploiting the nearby resources.

IsaacKuo
2007-Nov-01, 01:44 PM
Indeed, a lot of manufacturing processes need gravity. If you don't have gravity, you'll have to substitute in centrifuges, which can get much more complicated.

The entire habitat can be a huge centrifuge, providing about one gee of gravity near the outer floor.

Trakar
2007-Nov-01, 03:21 PM
Well, I like dried nori seaweed. ;)

You are welcome to all the pond scum you care to devour, I, personally, would find such, as a sole repast, distasteful and very quickly privatious.

Trakar
2007-Nov-01, 03:29 PM
What if we used one of those tether systems to deplete Jupiter's Van Allen Belt?

If we can't do that, Ganymede seems like a nice place.

The problem with aeroponics is that if your power goes out, you've got 20 minutes to fix the problem before all your plants die. With a rockwool system, you've got several hours to a couple of days to fix it.

Really, what's wrong with going organic? It wouldn't be hard to make your own soil by composting organic wastes and combining with the local dirt, and it would be a lot more fail-safe, besides tasting better.

This is simply incorrect, it would take a substantial time period before the plants would actually die, and this could be greatly extended by simply turning off the lighting system (and you could extend that to several days or weeks even by lowering the temperature). sprays every 20 minutes or so promote the most efficient/accelerated growth, but missing a few sprays is not going to kill the plants. Soil adds nothing to taste, it is only a means of supporting the plant's structure. Nothing wrong w/organic, it just isn't terribly efficient in an environment where weight and energy concerns are crucial.

Ronald Brak
2007-Nov-01, 04:00 PM
People seem rather concened with growing vegetables in space. It might be easier just to eat synthetic bacteria. Perhaps one set to break down human wastes and after a sterilization process to knock out most of the naturally occurring bacteria another set would be the actual food. They would be designed to be a complete meal with balanced quanities of carbohydates, protiens, fats and vitamins. Various methods could be used to make the bacterial sludge interesting to eat, or people could simply wear their VR goggles at mealtimes with a probe up their noses that releases aromatic compounds at the right moments.

IsaacKuo
2007-Nov-01, 04:09 PM
The Aztecs ate cyanobacteria cakes (http://en.wikipedia.org/wiki/Spirulina_%28dietary_supplement%29). It could be a useful primary food for space colonists.

Trakar
2007-Nov-01, 04:42 PM
Or a near-Earth asteroid. Technically it could even be done from Earth, at great expense.

There are several mass launch systems that are fairly economical w/regards to earth surface launch costs, once the systems are up and running. Especially if we are talking primarily about g-insensitive. And of course, if you can get around the irrational nuclear-phobia, things get a lot easier and cheaper, but such isn't likely.

Even sticking with fundementally standard chemical rocket launches, if they are done properly, can be very reasonable.

A Rocket a Day
Keeps the High Costs Away (http://www.fourmilab.ch/documents/rocketaday.html)

Trakar
2007-Nov-01, 04:51 PM
That's certainly news to me. Can you name names? Also, why think NEO asteroids have any more volatiles than will be found on the Moon, given that the perigees of most such asteroids are closer to the Sun than is the Moon's?

I just saw an astronaut on tv who was asked what are the best clothes to wear in space, and she said clothes with lots of pockets, because things tend to "fly everywhere". How many tools do you think NORAD is tracking that have been lost at the ISS?

Moon vs Asteroids (http://www.permanent.com/ep-a-v-l.htm)

Various cislunar delta-vs (http://uplink.space.com/showthreaded.php?Cat=&Board=missions&Number=23879&page=&view=&sb=&o=&vc=1)

NEO delta-vs (http://echo.jpl.nasa.gov/~lance/delta_v/delta_v.rendezvous.html)

Trakar
2007-Nov-01, 05:03 PM
People seem rather concened with growing vegetables in space. It might be easier just to eat synthetic bacteria. Perhaps one set to break down human wastes and after a sterilization process to knock out most of the naturally occurring bacteria another set would be the actual food. They would be designed to be a complete meal with balanced quanities of carbohydates, protiens, fats and vitamins. Various methods could be used to make the bacterial sludge interesting to eat, or people could simply wear their VR goggles at mealtimes with a probe up their noses that releases aromatic compounds at the right moments.

But the point is, most of what you seek to engineer, plants do by their nature. Why expend all the extra effort to make the basically raw materials interestingly and diversely edible and nutritious, when we have plants that are already programmed to do so with very little relative guidance and input from us?

IsaacKuo
2007-Nov-01, 05:20 PM
There are several mass launch systems that are fairly economical w/regards to earth surface launch costs, once the systems are up and running. Especially if we are talking primarily about g-insensitive. And of course, if you can get around the irrational nuclear-phobia, things get a lot easier and cheaper, but such isn't likely.

Why, exactly, would nuclear make anything a lot easier and cheaper? Nuclear power is expensive, even with low grade reactor fuel. The sort of high grade fuel suitable for nuclear bombs or nuclear rockets would be much more expensive.

I see nuclear electric as being an expensive option suitable for military vehicles that need the extra performance, but civilian applications would be almost entirely non-nuclear to avoid the extra costs.

Trakar
2007-Nov-01, 05:43 PM
Why, exactly, would nuclear make anything a lot easier and cheaper? Nuclear power is expensive, even with low grade reactor fuel. The sort of high grade fuel suitable for nuclear bombs or nuclear rockets would be much more expensive.

I see nuclear electric as being an expensive option suitable for military vehicles that need the extra performance, but civilian applications would be almost entirely non-nuclear to avoid the extra costs.

A nuclear powered vehicle can produce much higher levels of thrust for given vehicle and fuel masses, and lift much more payload. Nuclear fuel is relatively inexpensive in that a small amount goes a long way and like the energizer bunny keeps going, and going, and going.

IsaacKuo
2007-Nov-01, 05:56 PM
A nuclear powered vehicle can produce much higher levels of thrust for given vehicle and fuel masses, and lift much more payload.

Only if you use nuclear bombs, which are terribly expensive and don't scale down well. And have a lot of other issues.

With a nuclear reactor powered rocket, you have much less thrust and power than a chemical rocket. Chemical rockets have incredible power/weight ratios. Nuclear powered rockets are limited to low thrust, and only have an advantage over chemical rockets in that there's a higher potential exhaust velocity.

Except for nuclear bomb propulsion, nuclear powered rockets can't lift ANY payload against the 1 gee pull of gravity. In principle, a nuclear thermal rocket could achieve greater than 1 gee acceleration, but this possibility would involve as yet undeveloped technology.


Nuclear fuel is relatively inexpensive in that a small amount goes a long way and like the energizer bunny keeps going, and going, and going.

A small amount can go a long way, but even that small amount costs a whole heck of a lot. For space applications, solar is less expensive and it keeps going, and going, and going for even longer. Solar power technology just keeps on getting better and better, also. We're already at the point where solar power looks good for probes to Jupiter!

Trakar
2007-Nov-01, 08:03 PM
Only if you use nuclear bombs, which are terribly expensive and don't scale down well. And have a lot of other issues.

Actually it is quite scalable though impracticle in small scale for surface launch. The larger Orion systems are reasonable for a limited duration launch system.

Additionally, nuclear thermal systems are perfectly usable and without the open-air detonation issues of the orion systems.




With a nuclear reactor powered rocket, you have much less thrust and power than a chemical rocket. Chemical rockets have incredible power/weight ratios. Nuclear powered rockets are limited to low thrust, and only have an advantage over chemical rockets in that there's a higher potential exhaust velocity.!


Dumbo (http://www.dunnspace.com/00339489.pdf)

And this is a nearly 50 year old NTR design, it could be greatly improved upon in a modern redesign

Additionally there are numerous designs since which could easily be applied to a ground launch system if it were not for the general population nuclear-phobia.

The pebble bed Timberwind systems had a varient which weighed in at around 45 tons and produced 250 tons of thrust. A SSTO HLV system could easily be designed around a few of these.

And this doesn't even begin to get into the more paper-study designs like nuclear lightbulbs or the more advanced gas core systems.

IsaacKuo
2007-Nov-01, 08:59 PM
Actually it is quite scalable though impracticle in small scale for surface launch. The larger Orion systems are reasonable for a limited duration launch system.

It doesn't scale down well. You run into the minimum mass required for a nuclear bomb.


Additionally, nuclear thermal systems are perfectly usable and without the open-air detonation issues of the orion systems.

Nuclear thermal is not capable of the thrust required for surface launch. Not without undeveloped technology, at the very least. In order for nuclear thermal to be superior to chemical rockets on ANY level, it needs to use liquid hydrogen fuel. This, combined with the modest melting temperature of uranium, limits the potential performance. Chemical rockets can reach MUCH higher thrusts, and can reach higher exhaust velocity than nuclear thermal if anything other than hydrogen propellant is used.


Dumbo (http://www.dunnspace.com/00339489.pdf)

And this is a nearly 50 year old NTR design, it could be greatly improved upon in a modern redesign

Dumbo is a nearly 50 year old PROPOSAL. If it can work as hoped, and there are enough issues with hydrogen eroding all those channels to worry about it, then it could offer better thrust than NERVA. Enough better to provide a 1 gee acceleration? We can't say.


The pebble bed Timberwind systems had a varient which weighed in at around 45 tons and produced 250 tons of thrust. A SSTO HLV system could easily be designed around a few of these.

Actually, not so easy. First off, a pebble bed reactor has the same potential problems as Dumbo with hydrogen erosion. Second, the geometry of a pebble bed reactor implies a very non-streamlined irregular path for the propellant flow. That means losses which may or may not be as low as Timberwind hopes.

Third, and most damningly, 250 tons of thrust is only enough to provide 1 gee of acceleration if the loaded mass of the rocket is only 250 tons. That's for a rocket that can just barely lift itself off the ground. In order to actually go upward rather than hover, you may be limited to only 160 tons. Assuming a payload of 15 tons and 15 ton propellant tank, that gives us a mass ratio of only 160/75, or only 2.13. With a specific impulse of 1000 sec, that gives us a delta-v of only 7.4km/s--not enough to reach orbit!

Either way, we're still talking about the development of new technology that may or may not be proven. The basic problem is that you only get a performance boost using liquid hydrogen fuel--a fuel which is so problematic that many chemical rockets use less efficient kerosene instead. But in order to get high thrust out of propellant as lightweight as hydrogen, you need to heat it up a lot with a huge area of physical contact. That's a problem, because hot hydrogen is very unfriendly to most materials.


And this doesn't even begin to get into the more paper-study designs like nuclear lightbulbs or the more advanced gas core systems.

Nuclear lightbulbs and other gas core systems can't even dream of providing 1 gee of acceleration. They are strictly low acceleration proposals for use in deep space.

eburacum45
2007-Nov-01, 09:13 PM
O'Neill put rings of tiny agricultual cylinders around the outside of his Island Three concept habitat, which can be seen in this picture
http://www.orionsarm.com/civ/oneill1.jpg
these would be suitable for growing spirulina, and I suspect they wouldn't need to provide much gravity- just enough to stick the algae to the wall.

Van Rijn
2007-Nov-01, 09:58 PM
That's certainly news to me. Can you name names?


See here:

http://echo.jpl.nasa.gov/~lance/delta_v/delta_v.rendezvous.html

Look for anything with a delta-v below about 6 km/s, or look at the percentage comparison column.



Also, why think NEO asteroids have any more volatiles than will be found on the Moon, given that the perigees of most such asteroids are closer to the Sun than is the Moon's?


See my previous post here:

http://www.bautforum.com/1102382-post19.html

Warren Platts
2007-Nov-02, 01:09 AM
This is simply incorrect, it would take a substantial time period before the plants would actually die, and this could be greatly extended by simply turning off the lighting system (and you could extend that to several days or weeks even by lowering the temperature). sprays every 20 minutes or so promote the most efficient/accelerated growth, but missing a few sprays is not going to kill the plants. Soil adds nothing to taste, it is only a means of supporting the plant's structure. Nothing wrong w/organic, it just isn't terribly efficient in an environment where weight and energy concerns are crucial.Obviously, you've never tried aeroponics yourself, and it's equally obvious you've never tasted an organic product and a hydroponic product of the same strain side-by-side. Also, on the Moon, weight and energy won't be problems, because the soil and power sources will be made from local resources.

Noclevername
2007-Nov-02, 01:17 AM
Also, on the Moon, weight and energy won't be problems, because the soil and power sources will be made from local resources.
Soil can't be made from Lunar regolith, it requires both organic materials and a host of living components. Lunar materials can be used to form the nonorganic components of soil, but most of the makings of it would have to be imported, along with water. (aeroponics uses less water than soil farming.)

Ronald Brak
2007-Nov-02, 01:53 AM
But the point is, most of what you seek to engineer, plants do by their nature. Why expend all the extra effort to make the basically raw materials interestingly and diversely edible and nutritious, when we have plants that are already programmed to do so with very little relative guidance and input from us?

Wait, wait, I'll think of an answer, um... weight! Synthetic bacteria with a growth rate similar to algae but with much better nutritional value that only require human poop, CO2 and light would require much less weight to feed one human and (apart from energy intake) would make a closed or almost closed system much easier to construct.

And if you wanted to fool around long enough I'm sure you could develop methods of creating foods from synthetic life that mimic the tastes and texures of actual plants and animal meat and organs. In fact there's no reason why you can't grow meat that is actual meat except it came from a petri dish instead of an animal. We already do this a fair bit with human tissue for medical research.

And I don't see much extra effort involved. When are you going into space? If it's in more than 10 years we'll probably have lots of synthetic bacteria ready for you.

Noclevername
2007-Nov-02, 02:27 AM
And I don't see much extra effort involved. When are you going into space? If it's in more than 10 years we'll probably have lots of synthetic bacteria ready for you.

Well, I wouldn't take that for granted. Nor would I want a colony to rely on a new and untested biotechnology, there's already too many unknowns and things that might go wrong. The first space habitats will likely use tried-and-true food crops.

Warren Platts
2007-Nov-02, 02:29 AM
This is simply incorrect, it would take a substantial time period before the plants would actually die, and this could be greatly extended by simply turning off the lighting system (and you could extend that to several days or weeks even by lowering the temperature). sprays every 20 minutes or so promote the most efficient/accelerated growth, but missing a few sprays is not going to kill the plants. Soil adds nothing to taste, it is only a means of supporting the plant's structure. Nothing wrong w/organic, it just isn't terribly efficient in an environment where weight and energy concerns are crucial.
Obviously, you've never tried growing things with aeroponics yourself. If you do it right, the results are phenomenal, but there is no room for error. And equally obviously, you've never compared the taste of the same strain of vegetable grown in both organic and hydroponic conditions. And once you're set up on the Moon, weight and energy will not be a problem because organic soils and power supplies will be built from local materials.

Noclevername
2007-Nov-02, 02:30 AM
...

Should I re-post my reply?...

Warren Platts
2007-Nov-02, 03:41 AM
Moon vs Asteroids (http://www.permanent.com/ep-a-v-l.htm)

Various cislunar delta-vs (http://uplink.space.com/showthreaded.php?Cat=&Board=missions&Number=23879&page=&view=&sb=&o=&vc=1)

NEO delta-vs (http://echo.jpl.nasa.gov/~lance/delta_v/delta_v.rendezvous.html)


See here:

http://echo.jpl.nasa.gov/~lance/delta_v/delta_v.rendezvous.html

Look for anything with a delta-v below about 6 km/s, or look at the percentage comparison column.



See my previous post here:

http://www.bautforum.com/1102382-post19.html



Those are some cool links. :cool: Though the Moon's gravity well is a lot less that Earth's, it's still a lot more than an asteroid's, and so that translates into longer distances.

One thing about mining asteroids, however, is space debris.

You'd have to wrap a tarp around the whole job site. And if you're going to do that, you might as well pressurize the inside. Instant greenhouse. Heck, the asteroid might be more valuable as a greenhouse than as a mine!
:razz:

Noclevername
2007-Nov-02, 03:46 AM
You'd have to wrap a tarp around the whole job site. And if you're going to do that, you might as well pressurize the inside. Instant greenhouse. Heck, the asteroid might be more valuable as a greenhouse than as a mine!
:razz:

It's a cool idea. Unfortunately what little we know about the makeup of most NEOs indicates they're not exactly fertile ground. :sad:

Trakar
2007-Nov-02, 04:20 AM
It doesn't scale down well. You run into the minimum mass required for a nuclear bomb..

It scales down fine, you just have to use higher compressions on the fuel and/or higher initial neutron fluxes. reference the ICAN (http://www.engr.psu.edu/antimatter/Papers/ICAN.pdf)system. But as I said, the scaled down systems aren't practical for ground launch systems




Nuclear thermal is not capable of the thrust required for surface launch. Not without undeveloped technology, at the very least..

By the standards you are using an untested new design chemical rocket is "undeveloped" technology. The principles are virtually the same as the Nerva designs which were test fired, even pebble-bed systems have been static tested. The concepts being talked about would definitely require a bit more development, before they could be deployed, but so would any conventional rocket HLV design. And its not like what I'm talking about are pure, tenuously connected to reality, fantasies, like say a x-ray space battlecruiser.


In order for nuclear thermal to be superior to chemical rockets on ANY level, it needs to use liquid hydrogen fuel. This, combined with the modest melting temperature of uranium, limits the potential performance. Chemical rockets can reach MUCH higher thrusts, and can reach higher exhaust velocity than nuclear thermal if anything other than hydrogen propellant is used...

You need to better familiarize yourself with the technology and testing that has already been done. The uranium (or other fuel elements) for these types of cores are typically alloyed/integrated with carbide, zirconium and/or other high refractory materials. Here are a few introductory links, after you get up to speed with them I'll be happy to help you find some more involved material, and then we can discuss the subject at a more appropriate level of understanding.

Rover test series (http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19920005899_1992005899.pdf)

Good basic overview of many nuclear propulsion concepts (http://www-rsicc.ornl.gov/ANST_site/nasa10079.pdf)

Some basic NTR design (http://trajectory.grc.nasa.gov/aboutus/papers/AIAA-93-4170.pdf)

Good solid reference links page (http://anst.ans.org/RelatedLinks.html)

Mostly fun stuff, but several pieces that can help you to get a better feel for where the technology can lead. (http://www.nuclearspace.com/)

Trakar
2007-Nov-02, 04:26 AM
Obviously, you've never tried aeroponics yourself, and it's equally obvious you've never tasted an organic product and a hydroponic product of the same strain side-by-side.

Your assumptions are incorrect.


Also, on the Moon, weight and energy won't be problems, because the soil and power sources will be made from local resources.

My arguments are primarily in reference to orbital habitats and mostly, initial small orbital habitats.

Warren Platts
2007-Nov-02, 04:32 AM
Soil can't be made from Lunar regolith, it requires both organic materials and a host of living components.Some people on Earth say trees are the answer. In space, sewage is the answer. :D


Lunar materials can be used to form the nonorganic components of soil, but most of the makings of it would have to be imported, along with water. You should see some of the horrible soils farmers grow crops on here on Earth. Spray enough water and fertilize on plain lunar regolith, and you can grow just about anything. Rototill in composted sewage as it becomes available, after a few years you will have built up a rich soil that would be the envy of any gardener on Earth.

As for using up water, in a lunar colony, all water will constantly be recycled, so water is never "used up". If water was very tight, you'd probably want to go aeroponic, but if it's that bad, you'll just be growing a few salad greens like they do in Antarctica. Granted, I don't know where all the hydrogen is supposed to come from.

Hydrogen might be a product that a lunar base would like to buy from icy asteroids. Such water or methane would have to be hydrolized to remove the hydrogen that would then be shipped in liquid form.

One hundred thirty tons of imported hydrogen would make one acre-foot of water.

Trakar
2007-Nov-02, 04:41 AM
Granted, I don't know where all the hydrogen is supposed to come from.

Hydrogen might be a product that a lunar base would like to buy from icy asteroids. Such water or methane would have to be hydrolized to remove the hydrogen that would then be shipped in liquid form.

One hundred thirty tons of imported hydrogen would make one acre-foot of water.

How about using a magnetic trap to funnel in solar wind (mostly protons/ionized Hydrogen)? Yeah, you're not going to be pulling in huge amounts, but it should accumulate steadily and there's a lot of oxygen in the regolith. It'll be much easier if there is water at the poles. but failing that you're probably going to have to import most of it.

Warren Platts
2007-Nov-02, 04:43 AM
Your assumptions are incorrect.Schwheet! Send me some! :D

Noclevername
2007-Nov-02, 04:44 AM
Obviously, you've never seen some of the horrible soils farmers grow crops on here on Earth. Spray enough water and fertilize on plain lunar regolith, and you can grow just about anything. Rototill in composted sewage as it becomes available, after a few years you will have built up a rich soil that would be the envy of any gardener on Earth.


That's on Earth, with an entire biosphere attached. What you'd end up with may not be sustainable without all the action of insects, bacteria, worms, fungi, and all the other soil organisms that are in balance under your average patch of sod.

Warren Platts
2007-Nov-02, 04:46 AM
How about using a magnetic trap to funnel in solar wind (mostly protons/ionized Hydrogen)? Yeah, you're not going to be pulling in huge amounts, but it should accumulate steadily and there's a lot of oxygen in the regolith. It'll be much easier if there is water at the poles. but failing that you're probably going to have to import most of it.Someone here a while back did some calculations on capturing solar protons. IIRC, it's total hopeless--the absolute amount you could get is truly minute. :mad:

IsaacKuo
2007-Nov-02, 04:53 AM
It scales down fine, you just have to use higher compressions on the fuel and/or higher initial neutron fluxes. reference the ICAN (http://www.engr.psu.edu/antimatter/Papers/ICAN.pdf)system. But as I said, the scaled down systems aren't practical for ground launch systems

No. ICAN is a different concept. It doesn't use nuclear bombs, it uses anti-matter catalyzed reactions with magnetically compressed fuel pellets. It is also a low acceleration concept. Note that we've actually demonstrated nuclear bombs that work. We have NOT demonstrated anti-matter catalyzed nuclear reactions, nor have we actually manufactured sufficient quantities of anti-matter to even test the concept yet.


By the standards you are using an untested new design chemical rocket is "undeveloped" technology.

If it uses sufficiently novel techniques with difficult to resolve technical problems, then yes.


The principles are virtually the same as the Nerva designs which were test fired, even pebble-bed systems have been static tested. The concepts being talked about would definitely require a bit more development, before they could be deployed, but so would any conventional rocket HLV design.

I'm talking about known technical problems with high temperature hydrogen fuel flow. It's at least on the order of known problems with ion thruster electrode erosion. The ion thruster erosion problem has been reduced to levels where we're starting to be able to use them for interplanetary propulsion, but it took use decades of R&D to get this far.


And its not like what I'm talking about are pure, tenuously connected to reality, fantasies, like say a x-ray space battlecruiser.

A nuclear thermal rocket capable of SSTO is actually a pure fantasy. While it might be possible in principle to develop the technology to do it, it's never going to happen. The only way in principle would be to minimize shielding mass and that means venting neutrons directly into the atmosphere and thus generating radioactive fallout.

In contrast, the technologies for an X-ray laser armed space cruiser...well, they actually already exist. Not only that, but we're talking about technologies under intense active development both for big budget scientific purposes and commercial applications. The only major component which doesn't have any terrestrial civilian application is the high performance nuclear reactor. Civilian power reactors have extremely different design goals and operate in very different performance regimes. Military reactors are closer, but we're talking about a much smaller market.


You need to better familiarize yourself with the technology and testing that has already been done. The uranium (or other fuel elements) for these types of cores are typically alloyed/integrated with carbide, zirconium and/or other high refractory materials. Here are a few introductory links, after you get up to speed with them I'll be happy to help you find some more involved material, and then we can discuss the subject at a more appropriate level of understanding.

Oh, I've been reading up on nuclear thermal rocket engine papers since back when you had to do it in your university library.

One thing you need to understand about nuclear rocketry is that everyone already knows that a hot reactor venting neutrons into the atmosphere during surface launch is never going to happen, so all serious research is in terms of nuclear rockets that only fires up after leaving the atmosphere. In this performance regime, >1 gee acceleration is not needed, while minimizing system mass and maximizing efficiency are more important.

Warren Platts
2007-Nov-02, 04:53 AM
That's on Earth, with an entire biosphere attached. What you'd end up with may not be sustainable without all the action of insects, bacteria, worms, fungi, and all the other soil organisms that are in balance under your average patch of sod.But see, most commercial farmers have already destroyed the balance on their land. I used to have a buddy who was an organic farmer in Colorado, and you could go out into his vegetable field and get two handfuls of earthworms out of one shovel full of dirt.

But in nearby cornfields, it's impossible to even stick the shovel into the ground because it's practically rock hard, nasty, red clay crap that would grow nothing but a few sparse weeds on its own, but the center pivot irrigation and computer controlled liquid fertizer regimes produce huge crops of corn.

Basically, it is hydroponics, where the ground is used as a rooting medium rather than fancy rockwool.

IsaacKuo
2007-Nov-02, 04:57 AM
Granted, I don't know where all the hydrogen is supposed to come from.

There's also the question of where all the carbon comes from. Carbon based life forms kind of need carbon to add biomass.

Noclevername
2007-Nov-02, 04:59 AM
Some people on Earth say trees are the answer. In space, sewage is the answer. :D


So we ship sewage to the Moon? Easier to just ship food, it'll end up in that condition anyway...

Ronald Brak
2007-Nov-02, 05:21 AM
Well, I wouldn't take that for granted. Nor would I want a colony to rely on a new and untested biotechnology, there's already too many unknowns and things that might go wrong. The first space habitats will likely use tried-and-true food crops.

Growing plants in space is untested biotechnology too. I imagine that a couple of tanks that you plug into your toilet, power supply and CO2 scrubber might have less things that can go wrong with it than a farm that produces an equal amount of food. We can already do this with existing algae, however at the moment you are probably better off just taking packaged food and liquid oxygen with you on any space stay that isn't measured in years.

Noclevername
2007-Nov-02, 05:33 AM
Growing plants in space is untested biotechnology too.

Not to the same degree. And the ten-year delivery date isn't guaranteed either. Nor is twenty or thirty for that matter.

Ronald Brak
2007-Nov-02, 06:30 AM
Not to the same degree. And the ten-year delivery date isn't guaranteed either. Nor is twenty or thirty for that matter.

Well I have plenty of non-synthetic bacteria you can have in the mean time. I'm sending some to you right now through the internet. Just swab your screen and wipe it on some agar. They'll be there.

Ronald Brak
2007-Nov-02, 06:47 AM
There's also the question of where all the carbon comes from. Carbon based life forms kind of need carbon to add biomass.

For the lunar surface find some carbonous chondrite meteorite remains. Then see if you can find some water ice under the regolith at the poles or somewhere. Crack the carbon compounds into CO2, use that and the water to grow bean sprouts and other plants hydroponicly. Then mulch the plants and mix in lunar regolith plus a square centimeter or two of damp earth soil to "fertilize" it with fungi, bacteria and other little greeblies. Then see how that works as soil. You need to make sure you have adequate amounts of calcium, phosphorous and a handful of other elements. (Or you could try to make magnesium dominated soil if you wanted. Grow some sugar cane and some nice wattles.)

Noclevername
2007-Nov-02, 02:53 PM
For the lunar surface find some carbonous chondrite meteorite remains. Then see if you can find some water ice under the regolith at the poles or somewhere. Crack the carbon compounds into CO2, use that and the water to grow bean sprouts and other plants hydroponicly. Then mulch the plants and mix in lunar regolith plus a square centimeter or two of damp earth soil to "fertilize" it with fungi, bacteria and other little greeblies. Then see how that works as soil. You need to make sure you have adequate amounts of calcium, phosphorous and a handful of other elements. (Or you could try to make magnesium dominated soil if you wanted. Grow some sugar cane and some nice wattles.)

How much additional energy and time would it take to prospect for, mine, and transport all this stuff? If you can even find any in an accessible deposit? Better to bring what you need for the initial setup.

Warren Platts
2007-Nov-02, 06:59 PM
There's also the question of where all the carbon comes from. Carbon based life forms kind of need carbon to add biomass.
We also need nitrogen to make proteins.

Noclevername
2007-Nov-02, 07:08 PM
Then mulch the plants and mix in lunar regolith plus a square centimeter or two of damp earth soil to "fertilize" it with fungi, bacteria and other little greeblies.

Little greeblies that would still require the attentions of expert biologists and ecologists to be maintained in balance in a closed environment.

Noclevername
2007-Nov-03, 02:42 AM
So, IMO, space habitats will only happen after technology has improved to provide cheap space launch capability. Whether this is laser launch or kinetic impact rocket or whatever, I don't see it within the next century.

Wow, I know I'm dredging far back in the thread to dig this quote up (top of page 2) but it's worth addressing.

I've heard many people make the assumption that new technology is needed to bring down the cost of space travel. But one simple way it can be done-- not in a century, but more like within a decade or two-- is the mass production of cheap , simple boosters. This is the most cost-effective method using existing technology, and could reasonably be accomplished by any moderately wealthy industrialized nation. Only politics and limited thinking prevent it from happening now, or indeed prevented it from happening decades ago.

Don't be so quick to write this idea off, or dismiss it as a pipe dream. Trying to predict future technological developments is always uncertain; innovations don't happen on schedule. But all this method would require is a change of priorities. And as we all know, priorities can often change unexpectedly, especially when politics are involved.

Ronald Brak
2007-Nov-03, 03:11 AM
Little greeblies that would still require the attentions of expert biologists and ecologists to be maintained in balance in a closed environment.

Okay, back to the bacteria tanks then.

Ronald Brak
2007-Nov-03, 03:13 AM
Mind you, I've created a materially closed environment with lots of little greeblies in balance. It just wasn't one that could support human life.

Noclevername
2007-Nov-03, 03:15 AM
Mind you, I've created a materially closed environment with lots of little greeblies in balance. It just wasn't one that could support human life.

Yeah, we ruin everything, don't we? ;)

Ronald Brak
2007-Nov-03, 03:16 AM
I've heard many people make the assumption that new technology is needed to bring down the cost of space travel. But one simple way it can be done-- not in a century, but more like within a decade or two-- is the mass production of cheap , simple boosters. This is the most cost-effective method using existing technology, and could reasonably be accomplished by any moderately wealthy industrialized nation. Only politics and limited thinking prevent it from happening now, or indeed prevented it from happening decades ago.

This is true, however I would throw in economics there as a reason why it hasn't been done. But the Russians have demonsrated the savings that can be achieved with a good low cost, reliable design and there is plenty of room for further improvements and economics of scale. But the hard part is finding a market for these boosters.

Noclevername
2007-Nov-03, 03:24 AM
This is true, however I would throw in economics there as a reason why it hasn't been done. But the Russians have demonsrated the savings that can be achieved with a good low cost, reliable design and there is plenty of room for further improvements and economics of scale. But the hard part is finding a market for these boosters.

The main reason for the current lack of market demand is that everyone thinks of space travel as something massively expensive and inaccessible, limited only to huge government organizations. How many researchers, how many universities, would jump at the chance to buy a rocket trip to orbit if they knew they could afford it?

ADDED: And right now, even with present costs, millionaires are buying spaceflights as adventures/status symbols. How much will that number increase as the cost drops to half, a quarter, a tenth of what it is now?

Ronald Brak
2007-Nov-03, 03:32 AM
Well sounds like an opportunity for someone to build the Better Booster Company. Good luck.

Noclevername
2007-Nov-03, 03:37 AM
Well sounds like an opportunity for someone to build the Better Booster Company. Good luck.

It sure would be.

EDIT: Sadly, it seems like luck might be the only thing that actually gets more than a handful of people into space, or anyone beyond LEO, in my lifetime.

IsaacKuo
2007-Nov-03, 08:55 AM
I've heard many people make the assumption that new technology is needed to bring down the cost of space travel.

New technology is needed to dramatically reduce costs.


But one simple way it can be done-- not in a century, but more like within a decade or two-- is the mass production of cheap , simple boosters. This is the most cost-effective method using existing technology, and could reasonably be accomplished by any moderately wealthy industrialized nation. Only politics and limited thinking prevent it from happening now, or indeed prevented it from happening decades ago.

No, the main thing preventing it is limited demand for launches. Economies of scale require scale. The Russian boosters are already about as close as we can get to the cheap simple "mass" produced approach, for now. Given the limited launch demand, they're the only ones using basic booster designs old enough to be sorta "mass" produced.

The R&D for a new booster, no matter how simple and cheap, is going to add a lot of initial costs which put it at an economic disadvantage compared to simply producing more of an existing booster design.

That said, something like OTRAG could conceivably turn even limited launch demand into a mass production potential. OTRAG would have involved many identical modules per launch.

IsaacKuo
2007-Nov-03, 09:01 AM
The main reason for the current lack of market demand is that everyone thinks of space travel as something massively expensive and inaccessible, limited only to huge government organizations. How many researchers, how many universities, would jump at the chance to buy a rocket trip to orbit if they knew they could afford it?

ADDED: And right now, even with present costs, millionaires are buying spaceflights as adventures/status symbols. How much will that number increase as the cost drops to half, a quarter, a tenth of what it is now?

Those very few billionaires are doing so at discount rates from the Russians. The Russians are pretty much offering their services at bargain basement prices, using decades old boosters which were pretty cheap and simple to begin with and which have already paid for their R&D costs. It's hard to imagine any cheaper way to space, and it's not surprising that financially savvy billionaires would use the cheapest possible way to get to space.

Noclevername
2007-Nov-03, 09:16 AM
New technology is needed to dramatically reduce costs.

Define dramatically. Half? One third?


No, the main thing preventing it is limited demand for launches. Economies of scale require scale Addressed in my post above.


The Russian boosters are already about as close as we can get to the cheap simple "mass" produced approach, for now. Define "For now." Time frame?
Given the limited launch demand, Addressed above,
they're the only ones using basic booster designs old enough to be sorta "mass" produced.

The R&D for a new booster, no matter how simple and cheap, is going to add a lot of initial costs which put it at an economic disadvantage compared to simply producing more of an existing booster design.Initially.

That said, something like OTRAG could conceivably turn even limited launch demand into a mass production potential. OTRAG would have involved many identical modules per launch.
Wiki'd OTRAG, so what's its current status?

IsaacKuo
2007-Nov-03, 09:29 AM
Define dramatically. Half? One third?

Two orders of magnitude. Maybe a factor of 50+ reduction from today's Russian bargain basement prices.


Define "For now." Time frame? Addressed above, Initially.

For now means today.

A new launcher might change that, but a new launcher would take a few years to develop, and could take a decade to pay for its R&D costs.


Wiki'd OTRAG, so what's its current status?

Dead. And its tombstone isn't looking so hot either.

Noclevername
2007-Nov-03, 09:38 AM
Two orders of magnitude. Maybe a factor of 50+ reduction from today's Russian bargain basement prices.I've heard a lot of promises like that. Right now it's filed with flying cars and Rosie the Robot.



A new launcher might change that, but a new launcher would take a few years to develop, and could take a decade to pay for its R&D costs.
So? A decade is nothing. Certainly a lot less than the time it'll take to have a working laser launcher or orbital elevator, assuming we ever do.

Dead. And its tombstone isn't looking so hot either.

What does that mean?
From WP:
The necessary US$ 100 Million for the inventions and technological breakthroughs in rocket technology have been paid for in the last 30 years and are a solid foundation to proceed to CRPU mass production and clustered flights to qualify stage separation and orbital insertion for a 3-stage launcher.


...Explain the cause of death. Full autopsy.

IsaacKuo
2007-Nov-03, 09:55 AM
I've heard a lot of promises like that. Right now it's filed with flying cars and Rosie the Robot.

Oh, I don't PROMISE it. I'm asking for it. And I know that it's not going to happen without new technology.


So? A decade is nothing. Certainly a lot less than the time it'll take to have a working laser launcher or orbital elevator, assuming we ever do.

Oh, I wouldn't call a decade nothing. For example, I look at the last decade's worth of space missions and it looks like a lively decade to me. I eagerly look forward to the next decade also. Our technological progress is rather exciting also. Electric propulsion has hit prime time, enabling new missions like a double-asteroid visit. Solar panel technology has improved to the point of using them for Jupiter missions.

And lasers? We've gone from high energy lasers as pie-in-the-sky to practical in the last decade thanks to dielectric mirrors. We've gone through an entire generation of high energy laser technology with chemical reaction lasers outmoding gas electric lasers and themselves being outmoded by solid state lasers. The progress in the last decade has been phenomenal and continues to be phenomenal.

Heck, the progress of plain old chemical launchers in the last decade is nothing to sneeze at, either. One might argue that the field is too crowded, considering the limited demand, but it's perhaps better to have a little too much competition than too little.


What does that mean?...Explain the cause of death. Full autopsy.

OTRAG died decades ago. Supposedly it died because others didn't want West Germany to have rocket launch capability, or whatever. In any case, it's not like someone can just dust off the plans and take off, because if that were the case then Virgin Galactic or someone else would have already done it.

Noclevername
2007-Nov-03, 07:17 PM
Oh, I don't PROMISE it. I'm asking for it. And I know that it's not going to happen without new technology.

Agreed, which is why I'm talking about using present or easily achievable near-term technology to its fullest. Not could be, maybe, someday, if it works. Go with what we already know works now.


Oh, I wouldn't call a decade nothing. For example, I look at the last decade's worth of space missions and it looks like a lively decade to me. I eagerly look forward to the next decade also. Our technological progress is rather exciting also. Electric propulsion has hit prime time, enabling new missions like a double-asteroid visit. Solar panel technology has improved to the point of using them for Jupiter missions.

And lasers? We've gone from high energy lasers as pie-in-the-sky to practical in the last decade thanks to dielectric mirrors. We've gone through an entire generation of high energy laser technology with chemical reaction lasers outmoding gas electric lasers and themselves being outmoded by solid state lasers. The progress in the last decade has been phenomenal and continues to be phenomenal.

Heck, the progress of plain old chemical launchers in the last decade is nothing to sneeze at, either. One might argue that the field is too crowded, considering the limited demand, but it's perhaps better to have a little too much competition than too little.
Missing the point. You said
Whether this is laser launch or kinetic impact rocket or whatever, I don't see it within the next century.
Compared to the "next century" you mentioned, a decade isn't much.


OTRAG died decades ago. Supposedly it died because others didn't want West Germany to have rocket launch capability, or whatever. In any case, it's not like someone can just dust off the plans and take off, because if that were the case then Virgin Galactic or someone else would have already done it.
Details...? So far all I've heard are your opinions. I'd like some facts. What keeps this idea from being feasible? If it is feasible, what keeps it from being implemented? Legal restrictions? Politics?

Trakar
2007-Nov-03, 07:31 PM
Details...? So far all I've heard are your opinions. I'd like some facts. What keeps this idea from being feasible? If it is feasible, what keeps it from being implemented? Legal restrictions? Politics?

Insurance.
Reliablity issues come into play.
The system should work, but has an inherently higher failure rate.
Not a big deal if you're launching volumes of relatively cheap, mass products.
(sand, water, fuel, food, etc.,)
But losing 1 or 2 outta 10 commercial communications satellites or scientific probes makes it impossible to get enough clients to feed a rocket-a-day mass production system. Something like this needs a mandate to build a large orbital structure, before there are the guaranteed markets to support and drive the creation of a mass-produced (read as Cheap Access To Space) system.

Noclevername
2007-Nov-03, 07:53 PM
Insurance.
Reliablity issues come into play.
The system should work, but has an inherently higher failure rate.
Not a big deal if you're launching volumes of relatively cheap, mass products.
(sand, water, fuel, food, etc.,)
But losing 1 or 2 outta 10 commercial communications satellites or scientific probes makes it impossible to get enough clients to feed a rocket-a-day mass production system. Something like this needs a mandate to build a large orbital structure, before there are the guaranteed markets to support and drive the creation of a mass-produced (read as Cheap Access To Space) system.

Hm. With a failure rate that high, I guess not. :sad: Are there any ways to improve reliability?

Noclevername
2007-Nov-03, 09:29 PM
Even as-is, it might be used to deliver fuel to spacecraft bound for more distant destinations. The capacity to put a lot of fuel in orbit makes anyplace in the Inner Solar System reachable.

IsaacKuo
2007-Nov-03, 10:08 PM
Agreed, which is why I'm talking about using present or easily achievable near-term technology to its fullest. Not could be, maybe, someday, if it works. Go with what we already know works now.

Which means cheap Russian boosters, for now; maybe Delta IV tomorrow. Given the limited launch demand, we're making pretty good progress.


Missing the point. Compared to the "next century" you mentioned, a decade isn't much.

A decade is an entire tenth of a century. A decade here, a decade there, it adds up. A couple decades to reach the limits of chemical rocket boosters, a couple more decades for laser launch to even catch up for small payloads...another couple decades for laser launch to catch up for large payloads...another couple decades to reduce costs another order of magnitude...

It doesn't take all that long to reach a century, and that's assuming no particular stretch of stalled progress.


Details...? So far all I've heard are your opinions. I'd like some facts. What keeps this idea from being feasible? If it is feasible, what keeps it from being implemented? Legal restrictions? Politics?

Well, the death of OTRAG is one of those messy affairs with accusations all around. So opinions are about the best you can expect.

As for the facts--the big one is that no one has resurrected the concept, despite the fact that there are plenty of for-profit corporations which would LOVE to get a leg up on the competition.

Another fact is that OTRAG used a relatively low performance oxidizer which can't ever match the performance of LOX/kerosene or LOX/hydrogen. Even if you get OTRAG to work, it will never be an option for cheap launching of large amounts of cargo. In fact, the inefficiency of OTRAG would have been one of its features. Since even a small payload would require a huge mass ratio, there would have been potential for even a small launch demand to result in mass production economies of scale.

But those economies could only hope to compete with alternative boosters because the alternative boosters were so expensive. In the last three decades, though, space technology has not been standing still. Discount Russian boosters have become available to the West. Commercial boosters in the West have surpassed the Space Shuttle in economy.

Since we've refined LOX/hydrogen technology so well, it's perhaps only a matter of time before LOX/hydrogen eclipses the economic viability of good old LOX/kerosene boosters. As boosters like Delta-IV pay off their R&D, they'll get cheaper while the Russian booster prices have bottomed out. Is it already too late for boosters that don't even use LOX? Maybe so.

Or maybe there's some new technology which could beat the pants off of LOX/liquid hydrogen. Maybe hydrogen car research will provide some sort of lightweight hydrogen tanks? I dunno...carbon nanotubes are incredibly strong, possibly making compressed oxygen/compressed hydrogen tanks a viable technology. If so, then you can make almost comically simple boosters--no turbopumps, just a couple valves. The operating costs associated with cryogenic oxygen and hydrogen literally evaporate away.

In any case, we're talking new technology which will take time to develop.

Noclevername
2007-Nov-03, 10:18 PM
A couple decades to reach the limits of chemical rocket boosters, Which we have yet to approach. Which we could, with a concerted effort, in one or two decades rather than ten.


In any case, we're talking new technology which will take time to develop. But still far less so than laser launches and other spec-tech. *


As for the facts--the big one is that no one has resurrected the concept, despite the fact that there are plenty of for-profit corporations which would LOVE to get a leg up on the competition.
Nobody's done it yet, so it's not possible? Specious reasoning.


Another fact is that OTRAG used a relatively low performance oxidizer which can't ever match the performance of LOX/kerosene or LOX/hydrogen. Even if you get OTRAG to work, it will never be an option for cheap launching of large amounts of cargo. In fact, the inefficiency of OTRAG would have been one of its features. Since even a small payload would require a huge mass ratio, there would have been potential for even a small launch demand to result in mass production economies of scale.

But those economies could only hope to compete with alternative boosters because the alternative boosters were so expensive. In the last three decades, though, space technology has not been standing still. Discount Russian boosters have become available to the West. Commercial boosters in the West have surpassed the Space Shuttle in economy.
Not a difficult task, considering how uneconomical the Shuttle program is. But this trend has yet to run its course.


*Whoops, I moved that line and now it's out of context; IsaacKuo was referring to carbon-naotubes and similar tech.

Noclevername
2007-Nov-03, 10:29 PM
So it gets back to the question; How can a relatively cheap, but reliable, launcher become a reality anytime soon?

EDIT: Or rather, how can anyone who can afford it be encouraged to make it a reality?

IsaacKuo
2007-Nov-03, 10:33 PM
Which we have yet to approach. Which we could, with a concerted effort, in one or two decades rather than ten.

The limits of chemical rocket boosters, without "breakthrough" technologies, aren't going to be enough to make space colonization economical.


Nobody's done it yet, so it's not possible? Specious reasoning.

More like, nobody's done it yet, despite there being a number of greedy corporations which have the desire and resources to do it. Therefore it's not economical.


Not a difficult task, considering how uneconomical the Shuttle program is.

Actually, it was a difficult task to match the launch costs of the Space Shuttle with disposable boosters. The Russians did it by having their entire economy collapse (which devalued the ruble like nothing else). The Europeans and the greedy corporations did it by gradually improving technology decade by decade while the Space Shuttle stood still.

It's actually pretty remarkable how well the Space Shuttle has weathered the test of time. But it's plainly long in the tooth, and badly needs replacing.

Noclevername
2007-Nov-03, 10:42 PM
The limits of chemical rocket boosters, without "breakthrough" technologies, aren't going to be enough to make space colonization economical. Evidence...?




More like, nobody's done it yet, despite there being a number of greedy corporations which have the desire and resources to do it. Therefore it's not economical.
...You also forgot to mention limited imaginations. Corporations are run by businessmen, not engineers. Has everything that can be done, always been done? Do corporations always do the most practical thing? As long as their competitors make the same mistakes, they don't need to be as good as possible, only slightly better than the others.



It's actually pretty remarkable how well the Space Shuttle has weathered the test of time. But it's plainly long in the tooth, and badly needs replacing.

No argument there.

danscope
2007-Nov-04, 06:24 AM
Hi, Not for nuthin....but if the shuttle were entirely refurbished on site,
it would reduce costs. In other words , if every item were built locally , and I mean "Everything", you save an extraordinary amount in transport.
But.....as it is..... the money gets spent everywhere ( which spreads out the jobs , not unreasonable considering the money gets collected from such.
But....if you mass produced the boosters on site, cost go down. And we all know that we get a bunch of delta V from SRB's.
Yeah..thats the ticket. Maybe....maybe we could.........Nahhh! :)

With appologies to Steve Martin.

Noclevername
2007-Nov-04, 06:28 AM
There are a lot of things that can be done to reduce costs. Without compromising safety.


ADDED: Not that it matters. NASA is in no possition to disobey its overlords. Bureaucratic entropy wins this round.

danscope
2007-Nov-04, 06:39 AM
Ah...yes....entropy ...or something like it. Is it really compulsory in
areospace systems ?
Dan

Noclevername
2007-Nov-04, 06:48 AM
Ah...yes....entropy ...or something like it. Is it really compulsory in
areospace systems ?
Dan

Well, it is in human systems. Individuals can be good or bad, but large groups of people tend to suck.

danscope
2007-Nov-04, 06:52 AM
!!! LOL :) There is a high plausability in your assumtion.
Best regards, Dan

Van Rijn
2007-Nov-05, 11:22 AM
So it gets back to the question; How can a relatively cheap, but reliable, launcher become a reality anytime soon?

EDIT: Or rather, how can anyone who can afford it be encouraged to make it a reality?

Hopefully tourism will do that. I prefer the two stage reusable over the big dumb rocket approach. If you want to just put mass in space, mass producing rockets might be okay, but if you want a high flight rate for people, I think a reusable rocket designed for reliability and redundancy would make more sense.

Most of the cost is in operations, not fuel, so the trick is getting the operational cost down. Now, to get costs down to the equivalent of passenger air flight it probably would take new technology, but I see no reason why the cost couldn't come down radically compared to the current cost to get to orbit.

Noclevername
2007-Nov-05, 04:19 PM
If you want to just put mass in space, mass producing rockets might be okay, but if you want a high flight rate for people, I think a reusable rocket designed for reliability and redundancy would make more sense.

The more places to visit there are, the more tourists will want to go. Using cheap rockets to put up a space hotel, or better yet a well-supplied hotel-casino-theme park, with zero-g sports and 360-viewing domes, might inspire more work on making human-rated vehicles a reality.

Maybe. I don't know. Just a thought.

Noclevername
2007-Nov-05, 05:24 PM
If you add a very low-g spinning "swimming pool", the guests can have water-ball fights ;)

Noclevername
2007-Nov-12, 02:04 AM
One aspect of zero-g that's not often talked about is gas-- I mean digestive gas, not O2. Since there's nothing to bring air to the top of the stomach, not only do burps tend to bring up food, but air tends to get trapped in the digestive tract. A post-meal centrifuge may become a regular tradition.

danscope
2007-Nov-12, 02:27 AM
So....now you see the wisdom of a 2001 style space station..
Good. You show promise.

Noclevername
2007-Nov-12, 02:46 AM
So....now you see the wisdom of a 2001 style space station..
Good. You show promise.

Now? I did, right from the start. It's what I've been saying all along. Zero-g is for vacations, rotating stations are for everyday.

danscope
2007-Nov-12, 07:17 PM
Well said. Spining wheels.....got to go round .
Dan

Noclevername
2007-Nov-12, 07:21 PM
But until they're built, zero-g is what we're stuck with in space. So might as well make the most of it.

NiteWatcher
2007-Nov-13, 04:32 AM
I suppose my point is, human beings are animals that have unfathomable millions of years invested into their evolving to be fit for a certain type of environment, which is of course Earth. By and large, the bulk of our species lives in somewhat temperate climates that don't impose too many extremes on our bodies. There are obviously exceptions, like tiny teams of people living on Antarctica or in the middle of the Sahara, but for the most part these anomalies are not actual settled societies, but are instead transient groups. Most of the people on the planet live in places that are mild enough to not require special clothes for a large portion of the year.

If you study Arctic and Antarctic exploration history, you'll find in a literal nutshell what the psychological impact of stark environments will have to humans (even in this modern age).

Psychiatry hasn't even really touched on the madness that evolves without having a constant contact to sunlight (heck even the DSM-IVR classifies it as a "cultural" condition), that has plagued even Northern peoples who have adapted to that environment for thousands of years.

And if you think artificial sunlight is the "cure", there's a bridge in Brooklyn for sale. It's much more than sunlight that affects brain chemistry, let alone metabolism.

That's what those astronauts will face, all alone, without a rescue.

Sounds like some sci-fi horror flick, but it can happen, as it tends to affect more than one crewmember at a time.

And here we go, in mankind's zest to be "#1", all before he even understands his own body. Mars will be yet another Northwest Passage, with the same bleached bones and cairns to lure many another "star sailor" to their deaths.

Fame. Prestige. Ego will do that.

Warren Platts
2007-Nov-13, 05:51 AM
If you study Arctic and Antarctic exploration history, you'll find in a literal nutshell what the psychological impact of stark environments will have to humans (even in this modern age).

Psychiatry hasn't even really touched on the madness that evolves without having a constant contact to sunlight (heck even the DSM-IVR classifies it as a "cultural" condition), that has plagued even Northern peoples who have adapted to that environment for thousands of years.

And if you think artificial sunlight is the "cure", there's a bridge in Brooklyn for sale. It's much more than sunlight that affects brain chemistry, let alone metabolism.

That's what those astronauts will face, all alone, without a rescue.

Sounds like some sci-fi horror flick, but it can happen, as it tends to affect more than one crewmember at a time.

And here we go, in mankind's zest to be "#1", all before he even understands his own body. Mars will be yet another Northwest Passage, with the same bleached bones and cairns to lure many another "star sailor" to their deaths.

Fame. Prestige. Ego will do that.While Vikings and Englishmen were having a hard time with the Northwest Passage, the "Skraelings" up there managed pretty well for centuries with their stoneage technology.

Besides, there are a lots of worse ways to die than in a vain quest for fame and fortune on some bleak Martian desert at the bottom of Hellas crater--like drooling in some nursing home in front of a TV one can't even understand anymore. I'm still going!

NiteWatcher
2007-Nov-13, 06:13 AM
While Vikings and Englishmen were having a hard time with the Northwest Passage, the "Skraelings" up there managed pretty well for centuries with their stoneage technology.

Same dreams that keeps folks dying.


Besides, there are a lots of worse ways to die than in a vain quest for fame and fortune on some bleak Martian desert at the bottom of Hellas crater--like drooling in some nursing home in front of a TV one can't even understand anymore. I'm still going!

Dying on Mars may pose more problems than Romanticism: life itself.

Will we be polluters of other worlds, just so some "Smiling Al" can be Buck Rogers?

I don't have reservations about space flight or colonization (we have to get off this rock not for vanity, to prevent species extinction), I do have reservations when mankind attempts the feat before he's able to be responsible enough for his actions.

We have no rights to export our troubles beyond our world.

Warren Platts
2007-Nov-13, 06:25 AM
Same dreams that keeps folks dying.Indeed. . . . :D


Dying on Mars may pose more problems than Romanticism: life itself.

Will we be polluters of other worlds, just so some "Smiling Al" can be Buck Rogers?

I don't have reservations about space flight or colonization (we have to get off this rock not for vanity, to prevent species extinction), I do have reservations when mankind attempts the feat before he's able to be responsible enough for his actions.

We have no rights to export our troubles beyond our world.

Hence the importance of figuring out our space environmental ethics now! But I'm afraid trouble is endemic to the human condition. It's followed us throughout our history here, and I fear it will follow us into space as well. :boohoo:

BTW, Welcome to Bautforu, Nitewatcher!

NiteWatcher
2007-Nov-13, 09:51 AM
Hence the importance of figuring out our space environmental ethics now! But I'm afraid trouble is endemic to the human condition. It's followed us throughout our history here, and I fear it will follow us into space as well. :boohoo:

BTW, Welcome to Bautforu, Nitewatcher!

What "ethics"? Man can't even figure out what laws and ordinances are "right" on Earth, he'll won't figure it out for space. He'll demand freedom, then give excuses for not being responsible for said freedom.

Man's downfall will be himself in the end. Won't even need to worry about the Sun going nova, or an asteroid turning Earth into a doughnut.

Exporting "trouble" will only beget more of it, and Star Wars is only fun on TV.

We're not ready for space.

transreality
2007-Nov-13, 12:17 PM
They always send the wrong people on these missions. Why send the healthy action types? Send the nerds, the geeks and the nightclubbers, and goths! People who are used to not seeing the sun in huge chunks of time from a very early age. ;)

Noclevername
2007-Nov-13, 05:49 PM
He'll demand freedom, then give excuses for not being responsible for said freedom.
<Snip>
We're not ready for space.

Got it backwards. In a space habitat, the penalty for irresponsibility is death, self-enforced. A limited life-support system requiring constant maintainance is a demanding teacher. Space will make us ready, by the only method proven to teach-- survival.

danscope
2007-Nov-13, 10:57 PM
[QUOTE=Warren Platts



Hence the importance of figuring out our space environmental ethics now! But I'm afraid trouble is endemic to the human condition. It's followed us throughout our history here, and I fear it will follow us into space as well.

......." Where ever there is trouble, you will find us.
"wherever there is suffering,...we'll be there."
........" Whenever there is misery , look for us...."
Dan

Noclevername
2007-Nov-13, 11:27 PM
We're never going to even come close to getting our act together as long as we're crammed on one globe scrabbling over scraps. Getting into space won't solve our problems, but it will put humanity into a position of unlimited resources, unlimited living space, and room to get away from each other. This will make it possible to experiment socially on a scale we've never had before. Try enough variations, and you're sure to find some that work well.

MentalAvenger
2007-Nov-14, 04:31 AM
We're never going to even come close to getting our act together as long as we're crammed on one globe scrabbling over scraps. Getting into space won't solve our problems, but it will put humanity into a position of unlimited resources, unlimited living space, and room to get away from each other. This will make it possible to experiment socially on a scale we've never had before. Try enough variations, and you're sure to find some that work well.Interesting observation, there may be a lot of truth in that. Only a few observations. We currently have (for all practical purposes) unlimited resources. We live on an 8000 mile diameter ball of resources. True, most of that is molten rock, but that doesn’t mean it is totally inaccessible as resources. In the meantime, the solid crust of the Earth contains everything we need in quantities far above what we will be able to use within the next 1000 years or so. Some of those resources are getting more difficult to extract, but they are there. (Remember, most of the concentrated rare materials are the result of asteroid or comet impacts, and we have found only a small portion of those concentrations that occurred on the land masses. We must assume that there are something like 3 times that amount of concentrated materials in the various oceans around the world.)

Historically (essentially) unlimited resources only resulted in a small section of the Earth’s population really benefiting from those resources. The United States of America became so powerful so quickly because of the easy availability of so many different resources. It is unlikely that will happen in space, since extraction and refining of any materials in space will be both time and labor intensive. The time intensive refers to the long travel times between potential sources (planets, asteroids, comets, etc.).

Noclevername
2007-Nov-14, 04:42 AM
Extracting resources from inaccessible parts of Earth is no easier and will require at least as much time and research to implement.


It is unlikely that will happen in space, since extraction and refining of any materials in space will be both time and labor intensive. The time intensive refers to the long travel times between potential sources (planets, asteroids, comets, etc.).

At first, yes. But at present we're only in the infancy of space travel. It's certainly possible that in the near future we will be able to, say, exceed the travel time to reach our colonies of the vast empires of the age of sail. And as technology improves, we will go even faster. But of course, it's certainly possible right now to find concentrations of resources, such as medium-sized Carbonaceous asteroids, that contain all the materials needed to support a human habitation for long periods. Extracting them will be slightly easier (once the processes used are properly engineered) since there's access to easy energy and no need to worry about damaging the environment, not to mention that by the time asteroid mining can actually be done on a useful scale, robotic and automated mining and manufacturing technologies will have improved as well.

MentalAvenger
2007-Nov-14, 04:59 AM
Extracting resources from inaccessible parts of Earth is no easier and will require at least as much time and research to implement. Not clear on what you mean by that. No easier than what? If you are saying it is no easier than extracting and refining materials from asteroids and comets, I’d have to say you are wrong by many orders of magnitude. If not, please explain.


At first, yes. But at present we're only in the infancy of space travel. It's certainly possible that in the near future we will be able to, say, exceed the travel time to reach our colonies of the vast empires of the age of sail. People see animated or still representations of our Solar system and they think that it is easy to get from one place to another, because it doesn’t look that far. It is far. Regardless of the technology developed, it will require a certain amount of energy to go a certain distance in a certain amount of time. No way around that. While the concentration of energy may increase, the amount of total energy required remains the same. Moving across the Solar system to mine, refine, and ship materials, with be expensive and very time consuming. And in the end, it will only be practical to use those materials in space.


And as technology improves, we will go even faster. But of course, it's certainly possible right now to find concentrations of resources, such as medium-sized Carbonaceous asteroids, that contain all the materials needed to support a human habitation for long periods. If you want to live on an asteroid, where you may weight half a gram.


Extracting them will be slightly easier (once the processes used are properly engineered) since there's access to easy energy and no need to worry about damaging the environment, not to mention that by the time asteroid mining can actually be done on a useful scale, robotic and automated mining and manufacturing technologies will have improved as well. Ah, the holy grail of all asteroid mining advocates. If such totally automated robotic mining and processing were so easy, we would already be doing it on Earth. We are not.

Noclevername
2007-Nov-14, 05:24 AM
Not clear on what you mean by that. No easier than what? If you are saying it is no easier than extracting and refining materials from asteroids and comets, I’d have to say you are wrong by many orders of magnitude. If not, please explain.
That is what I mean, and it is true. Getting to the less accessible parts of our own planet is not as easy as you imply, especially the parts we're still living on.

People see animated or still representations of our Solar system and they think that it is easy to get from one place to another, because it doesn’t look that far. It is far. Regardless of the technology developed, it will require a certain amount of energy to go a certain distance in a certain amount of time. No way around that. While the concentration of energy may increase, the amount of total energy required remains the same. Moving across the Solar system to mine, refine, and ship materials, with be expensive and very time consuming. Not forever, no. And energy considerations will be less limiting when we can build arbitrarily large solar collectors.
And in the end, it will only be practical to use those materials in space.
Great, that's where I'd want to use them.

If you want to live on an asteroid, where you may weight half a gram.
Or on a rotating space station next to an asteroid, where you can weight whatever you choose, up to and including 1g equivalent.


Ah, the holy grail of all asteroid mining advocates. If such totally automated robotic mining and processing were so easy, we would already be doing it on Earth. We are not.
I see you skipped lightly over the part where I said "not to mention that by the time asteroid mining can actually be done on a useful scale, robotic and automated mining and manufacturing technologies will have improved as well." Improved. If improvement of technology is a "holy grail", they must give them out like paper cups.

Mining on an asteroid, at least for certain kinds of mining, may be easier to accomplish remotely that it ever could be on Earth, because many asteroids appear to be loose rubble piles. In asteroidal micro-g, you don't need to worry about tunnels collapsing or caving in. You don't need tunnels at all in fact, as there's no ecological considerations to prevent strip-mining. Which in this case will consist of scooping up sand and pebbles.

Noclevername
2007-Nov-14, 05:28 AM
In any case, one resource we definitely do not have on our one planet is unlimited living space. That can only be found offplanet. And developing the capacity to survive there will take time. Put that learning process off now, and you'll still need to take the time to do it later.

Van Rijn
2007-Nov-14, 05:35 AM
People see animated or still representations of our Solar system and they think that it is easy to get from one place to another, because it doesn’t look that far. It is far. Regardless of the technology developed, it will require a certain amount of energy to go a certain distance in a certain amount of time. No way around that. While the concentration of energy may increase, the amount of total energy required remains the same. Moving across the Solar system to mine, refine, and ship materials, with be expensive and very time consuming. And in the end, it will only be practical to use those materials in space.


I agree most material mined in space will be used there. However, there could be some exceptions, such as platinum. Regardless, it could substantially reduce costs of development in orbit relatively soon. Also, travel time isn't as big an issue as delta v requirements and difficulty of access (it's easier to reach the surface of many asteroids than the surface of Mars or the Moon).



If you want to live on an asteroid, where you may weight half a gram.


Or you build a rotating space habitat, which could provide a more earthlike environment than a habitat on Mars.



Ah, the holy grail of all asteroid mining advocates. If such totally automated robotic mining and processing were so easy, we would already be doing it on Earth. We are not.

Not a valid comparison. Neither the issues or conditions are the same. An expanded robotic sample return vehicle could go to a carbonaceous asteroid to pick up material (which may well be loose) to take back to earth orbit for processing. For a growing presence in Earth orbit, a small fleet of such robot ships could be far cheaper than bringing the material up from Earth. The economics on Earth (where people are plentiful and there is air) is quite a bit different for conventional mining. Even so, I expect the level of automation in countries with high labor costs will increase markedly in the next decade or two.

Van Rijn
2007-Nov-14, 05:51 AM
Got it backwards. In a space habitat, the penalty for irresponsibility is death, self-enforced. A limited life-support system requiring constant maintainance is a demanding teacher. Space will make us ready, by the only method proven to teach-- survival.

One of the interesting aspects of that is that we have a great deal to learn about building small, tight, closed ecologies. The fact is that we just don't have that much incentive to do the research on tight, complex ecologies unless we plan to live in them. I expect there will be whole new aspects to ecological science and an entire profession of ecological engineers when we get around to building space habitats we actually intend to live in long term. The knowledge gained that way would be extremely valuable back here on good old earth. After all, if you have to learn how to keep a small ecology going well, where there is almost no room for error, imagine how useful that would be on Earth.

Noclevername
2007-Nov-14, 07:47 PM
One of the interesting aspects of that is that we have a great deal to learn about building small, tight, closed ecologies.

It's definitely the major sticking point for creating space colonies that can be truly self-sufficient. All the other aspects can be accomplised using either existing technology or modified/engineered versions of existing technology. This is the one part we really can't do without, it's where the most research is needed, and it's where the least has been done.

MentalAvenger
2007-Nov-15, 07:20 PM
That is what I mean, [that extracting resources from inaccessible parts of Earth is no easier than extracting and refining materials from asteroids and comets] and it is true. Getting to the less accessible parts of our own planet is not as easy as you imply, especially the parts we're still living on.But IMO still far far easier than getting those materials from asteroids and comets. All else being equal, travel time, energy required, time delay for robotic control, etc. will make asteroid mining much more complicated, time consuming, and expensive. And if you are talking about manned missions to mine asteroids, the differences in wages alone would be astronomical.


Not forever, no. Of course not. I was referring to the practical future, say within 200 years or so.


Or on a rotating space station next to an asteroid, where you can weight whatever you choose, up to and including 1g equivalent. The cost of constructing and/or moving such a station to an asteroid merely for the comfort of the miners would make it impractical.

Noclevername
2007-Nov-15, 07:26 PM
But IMO still far far easier than getting those materials from asteroids and comets. All else being equal, travel time, energy required, time delay for robotic control, etc. will make asteroid mining much more complicated, time consuming, and expensive. And if you are talking about manned missions to mine asteroids, the differences in wages alone would be astronomical.

Of course not. I was referring to the practical future, say within 200 years or so.

The cost of constructing and/or moving such a station to an asteroid merely for the comfort of the miners would make it impractical.

As long as you recognize that these are just speculative opinions, I have no problem with your ststements. I just disagree with them.

(Especially that last one, as many NEOs are reachable with less delta-v than a trip to the Moon.)

danscope
2007-Nov-15, 07:26 PM
I agree most material mined in space will be used there. However, there could be some exceptions, such as platinum. Regardless, it could substantially reduce costs of development in orbit relatively soon. Also, travel time isn't as big an issue as delta v requirements and difficulty of access (it's easier to reach the surface of many asteroids than the surface of Mars or the Moon).



Or you build a rotating space habitat, which could provide a more earthlike environment than a habitat on Mars.



Not a valid comparison. Neither the issues or conditions are the same. An expanded robotic sample return vehicle could go to a carbonaceous asteroid to pick up material (which may well be loose) to take back to earth orbit for processing. For a growing presence in Earth orbit, a small fleet of such robot ships could be far cheaper than bringing the material up from Earth. The economics on Earth (where people are plentiful and there is air) is quite a bit different for conventional mining. Even so, I expect the level of automation in countries with high labor costs will increase markedly in the next decade or two.

Hi, If you want to define the typical module by area and length,diameter,
I should think the Shuttle main tank is a reasonable size....for many reasons.
Why jettison such a usefull resource? It simply makes sense.
Best regards, Dan

MentalAvenger
2007-Nov-15, 07:28 PM
In any case, one resource we definitely do not have on our one planet is unlimited living space. That can only be found offplanet.Moving into space will not significantly affect living space on Earth. The few people who do move off-Earth will no doubt increase their numbers naturally, but at first at a slower rate than on Earth (due to limited resources). That small number of pioneer will have virtually no measurable impact on the remaining population or how they continue to increase the population. It is unlikely that there will ever come a time when technology and resources will allow the leaving of a number of pioneers that would have an even slightly significant impact on Earth’s population.

Noclevername
2007-Nov-15, 07:30 PM
Hi, If you want to define the typical module by area and length,diameter,
I should think the Shuttle main tank is a reasonable size....for many reasons.
Why jettison such a usefull resource? It simply makes sense.
Best regards, Dan

It's been suggested many times-- by me, for one --the standard response I've heard is that putting a tank in a high enough orbit not to decay in a decade would require more fuel and be expensive.

(Personally I think an extra set of solid boosters on the tank would easily do the job. But I don't have the math or engineering to back it up so I just sit quietly and fume at all the wasted value.)

MentalAvenger
2007-Nov-15, 07:34 PM
Not a valid comparison. Neither the issues or conditions are the same. An expanded robotic sample return vehicle could go to a carbonaceous asteroid to pick up material (which may well be loose) to take back to earth orbit for processing. For a growing presence in Earth orbit, a small fleet of such robot ships could be far cheaper than bringing the material up from Earth. Of course. But IMO, the Moon would be a far easier place to mine materials and process them. Due to the number of asteroid and comet impacts, there are probably nice concentrations of materials all over the Moon. The point is, the Moon would provide a better place to process materials, and better (and cheaper) living conditions for those who have to tend the equipment.

MentalAvenger
2007-Nov-15, 07:38 PM
It's been suggested many times-- by me, for one --the standard response I've heard is that putting a tank in a high enough orbit not to decay in a decade would require more fuel and be expensive. Actually, IIRC, the shuttle has to perform a special maneuver just to make the sure the ET goes back down and burns up. Otherwise, the ET would often tend to go into its own orbit. After lifting that much mass up from Earth and accelerating it to orbital velocity, the amount of energy required to boost it a little more is trivial.

danscope
2007-Nov-15, 08:01 PM
It's been suggested many times-- by me, for one --the standard response I've heard is that putting a tank in a high enough orbit not to decay in a decade would require more fuel and be expensive.

(Personally I think an extra set of solid boosters on the tank would easily do the job. But I don't have the math or engineering to back it up so I just sit quietly and fume at all the wasted value.)

Hi, Yes, I believe you have it right: Configure the system with more SRB's
Not easy, but not impossible ) and save the main tank for usefull purpose.
Twelve shuttle tanks make a big circle....and how. This will yield a diameter
in excess of 600 meters.
Best regards, Dan

Noclevername
2007-Nov-15, 08:01 PM
Moving into space will not significantly affect living space on Earth. The few people who do move off-Earth will no doubt increase their numbers naturally, but at first at a slower rate than on Earth (due to limited resources). That small number of pioneer will have virtually no measurable impact on the remaining population or how they continue to increase the population. It is unlikely that there will ever come a time when technology and resources will allow the leaving of a number of pioneers that would have an even slightly significant impact on Earth’s population.

I've been over this before on another thread, but... I said nothing about living space or population on Earth. Only those who live in space can get the benefits from living in space.

MentalAvenger
2007-Nov-15, 10:58 PM
Sorry, the comment we definitely do not have on our one planet is unlimited living space, in context with a discussion about moving into space, seemed to insinuate a relief from that unlimited living space on Earth. My mistake.

Noclevername
2007-Nov-15, 11:09 PM
Sorry, the comment we definitely do not have on our one planet is unlimited living space, in context with a discussion about moving into space, seemed to insinuate a relief from that unlimited living space on Earth. My mistake.

No problem. I tried to word it clearly, but sometimes that skill escapes me. To sum it up as best I can; "The living space available off-Earth can't come to us, we have to go to it." ;)

ADDED: And we have to build it once we get there. I should've said potential living space, right now it's just space. Okay, so this attempt didn't make it clear either. D'oh.

Noclevername
2007-Nov-15, 11:36 PM
Of course. But IMO, the Moon would be a far easier place to mine materials and process them. Due to the number of asteroid and comet impacts, there are probably nice concentrations of materials all over the Moon.
Which would still need to be prospected and dug up.


The point is, the Moon would provide a better place to process materials, and better (and cheaper) living conditions for those who have to tend the equipment.

What do you believe makes the Moon a better place than a Near Earth asteroid?

MentalAvenger
2007-Nov-16, 12:55 AM
IMO, it is unlikely that humans will tolerate micro-G for extended periods of time. Also, it would not be practical to supply a space station large enough to provide artificial gravity to each asteroid. Therefore, living conditions for asteroid mining would not be favorable to humans. Although we don’t have data on it yet, it seems reasonable that 1/6th G would be a lot healthier than micro-G. It is possible that humans could tolerate 1/6th G indefinitely. Regardless, the safe period would be a LOT longer than on an asteroid, IMO.

Reaching an asteroid, even if it passes close to the Earth, would require almost as much acceleration as going to Mars. (depending on the specific asteroid) Bringing materials back would require equal deceleration, each and every time. In addition, for most of the time, the asteroid would be far from the Earth. Depending upon the orbital path, that could put it out beyond useable sunlight for much of its orbit. Bases on the Moon would be permanent and stable, and always close to the Earth. For at least 50% of the time, they would have intense sunlight available. Collectors at the poles could provide power 24/7.

Mining and processing operations will require a lot of support. It would be a lot easier to provide that support with a colony on the Moon, including living spaces, food, maintenance, supply depots, recreation, social functions, etc, all of which would require a minimum population of a colony. That is not something that would be practical on an asteroid.

There are other reasons.

Van Rijn
2007-Nov-16, 01:44 AM
IMO, it is unlikely that humans will tolerate micro-G for extended periods of time. Also, it would not be practical to supply a space station large enough to provide artificial gravity to each asteroid. Therefore, living conditions for asteroid mining would not be favorable to humans. Although we don’t have data on it yet, it seems reasonable that 1/6th G would be a lot healthier than micro-G. It is possible that humans could tolerate 1/6th G indefinitely. Regardless, the safe period would be a LOT longer than on an asteroid, IMO.


Why are you sending people to an asteroid? Noclevername and I have been talking about robot missions to the asteroids. They bring the material to be processed in orbit. If you need a rotating space station you build it in Earth orbit, and you can have pseudogravity the same as Earth's.



Reaching an asteroid, even if it passes close to the Earth, would require almost as much acceleration as going to Mars. (depending on the specific asteroid)


See here:

http://echo.jpl.nasa.gov/~lance/delta_v/delta_v.rendezvous.html

There are 681 known asteroids that require less delta-v to reach from LEO than the moon, and there are 1005 known asteroids that require less delta-v than Mars. At the low end, you can reach some for about 2/3 the delta-v. That's a rather large difference. Also, no rapid accelerations are required, unlike landing on the Moon or Mars.



Bringing materials back would require equal deceleration, each and every time.


If you're bring material back to Earth orbit, the total delta-v budget is lower for the asteroids listed above than going to and returning from the Moon or Mars.



In addition, for most of the time, the asteroid would be far from the Earth. Depending upon the orbital path, that could put it out beyond useable sunlight for much of its orbit.


Not true. These are NEO asteroids.



Bases on the Moon would be permanent and stable, and always close to the Earth. For at least 50% of the time, they would have intense sunlight available. Collectors at the poles could provide power 24/7.


Depending on the rotation axis of the asteroid and the landing point, it too might provide 24/7 sunlight. In any event, it's doubtful there are many asteroids with two week long nights.



Mining and processing operations will require a lot of support. It would be a lot easier to provide that support with a colony on the Moon, including living spaces, food, maintenance, supply depots, recreation, social functions, etc, all of which would require a minimum population of a colony. That is not something that would be practical on an asteroid.


Again, you're assuming that people would be sent to the asteroid.



There are other reasons.

But not terribly persuasive. The key advantage for the moon is time: It's quicker to get there. However, it is known that the moon is poor in volatiles. The key advantage to NEOs are that some would be rich in materials that would be hard to get on the moon, and some are easier to reach than the moon. A relatively simple expanded sample return mission to an asteroid could start supplying material for earth orbit development without any dramatic leaps in technology. It could be a fairly low budget and relatively near term development.

MentalAvenger
2007-Nov-16, 05:37 AM
Why are you sending people to an asteroid? Noclevername and I have been talking about robot missions to the asteroids. Oh, I thought we were talking about sometime in the near future, not far in the future when robot technology finally allows such missions. We could mine the Moon with today’s technology.


They bring the material to be processed in orbit. Considering the machinery and materials required for turning ore into finished products, I don’t think orbital stations would be practical. considering how relatively expensive and inherently fragile space stations will be, using them to smelt iron and extract aluminum would be prohibitively expensive. Those are the materials that will be needed most as we begin to build spacecraft in space instead of boosting them from Earth. The Moon would be a great place for that.


At the low end, you can reach some for about 2/3 the delta-v. That's a rather large difference. And at the high end, it is the same. Now, let’s see, didn’t I say ”almost”? Yep, I did.


If you're bring material back to Earth orbit, the total delta-v budget is lower for the asteroids listed above than going to and returning from the Moon or Mars.
For materials mined on the Moon, there would be no delta V at all, because they would be processed right there. Also, there is a LARGE difference in mass between ore and finished product.


Not true. These are NEO asteroids. I stand corrected.


Depending on the rotation axis of the asteroid and the landing point, it too might provide 24/7 sunlight. AFAIK, virtually all asteroids rotate, many in three axis, and some very rapidly. That would make solar collecting difficult.


Again, you're assuming that people would be sent to the asteroid. Again, I was assuming this was something that would be done as we began moving out, not later on. Robot technology has advanced greatly, but even our best robots require a lot of care and a lot of supervision.


The key advantage for the moon is time: It's quicker to get there. The main advantage is that it would be quicker, easier, and cheaper to build a viable support colony on the Moon than on a space station.


The key advantage to NEOs are that some would be rich in materials that would be hard to get on the moon When they hit the Moon, those same materials are deposited there.


A relatively simple expanded sample return mission to an asteroid could start supplying material for earth orbit development without any dramatic leaps in technology. It could be a fairly low budget and relatively near term development. Again, moving ore across those distances would not be very efficient. Depending upon the concentration, you could well be moving 10-20 times as much material as needed, unless your robot can also figure out how (and have the capability) to separate the ore from the rocks etc.

Van Rijn
2007-Nov-16, 08:53 AM
Oh, I thought we were talking about sometime in the near future, not far in the future when robot technology finally allows such missions. We could mine the Moon with today’s technology.


I was talking about the near future. Just what do you think is needed to pick up (quite possibly loose, or lightly held) material from an asteroid? Actually, part of the point of asteroid mining is because they are easier for a robot to reach, and return from with material, than the moon.




Considering the machinery and materials required for turning ore into finished products, I don’t think orbital stations would be practical.


I'm getting the feeling (actually, I've had it for a while now) that you're being contradictory just for the heck of it. The only difference between the moon and an orbital station is that gravity is optional on an orbital station.



And at the high end, it is the same. Now, let’s see, didn’t I say ”almost”? Yep, I did.


And at the low end, it isn't. If you think that two thirds is almost the same you have a rather broad definition of the term.



For materials mined on the Moon, there would be no delta V at all, because they would be processed right there.


Assuming you're using it on the moon. I thought we were talking about use in Earth orbit. My concern, if it wasn't clear, was reducing the cost of maintenance and expansion of facilities in Earth orbit over the relatively near term (next few decades).



Also, there is a LARGE difference in mass between ore and finished product.


For material returned from (for example) a carbonaceous asteroid, pretty much everything would be useful to a facility in orbit. A stony asteroid would have more silicon dioxide, but even that would be useful in orbit: oxygen for air, silicon for IC cells, etc. At worst, any extra material would be useful for radiation protection (which will become important for long term habitation, especially if not in LEO).



AFAIK, virtually all asteroids rotate, many in three axis, and some very rapidly. That would make solar collecting difficult.


At most, a rapid rotation would means you wouldn't attempt to aim the solar panels.



Again, I was assuming this was something that would be done as we began moving out, not later on. Robot technology has advanced greatly, but even our best robots require a lot of care and a lot of supervision.


. . . which can be done from Earth, just as we do with the two long lived Martian rovers. Again, I was assuming current or near current technology.




The main advantage is that it would be quicker, easier, and cheaper to build a viable support colony on the Moon than on a space station.


Not if you are supporting facilities in orbit.



When they hit the Moon, those same materials are deposited there.


Do you have evidence of this? It isn't clear that volatiles will be usefully accessible on the moon. But even if they are, it's still easier to reach many asteroids.

Noclevername
2007-Nov-16, 11:25 AM
Also, it would not be practical to supply a space station large enough to provide artificial gravity to each asteroid.
Impractical in what way? It's no more or less difficult that keeping a Moonbase supplied and/or making one that's self-sufficient.

EDIT: On re-reading I realize that last sentence is a bit unclear. What I mean is that supplying a Moonbase or a space habitat is equal in difficulty, and making a Moonbase or space habitat self-sufficient are equal in difficulty, not that they're all the same difficulty. Confused? I know I am.


Therefore, living conditions for asteroid mining would not be favorable to humans. Although we don’t have data on it yet, it seems reasonable that 1/6th G would be a lot healthier than micro-G. It is possible that humans could tolerate 1/6th G indefinitely. Regardless, the safe period would be a LOT longer than on an asteroid, IMO.
Reaching an asteroid, even if it passes close to the Earth, would require almost as much acceleration as going to Mars. (depending on the specific asteroid) Bringing materials back would require equal deceleration, each and every time. In addition, for most of the time, the asteroid would be far from the Earth. Depending upon the orbital path, that could put it out beyond useable sunlight for much of its orbit. Bases on the Moon would be permanent and stable, and always close to the Earth. For at least 50% of the time, they would have intense sunlight available. Collectors at the poles could provide power 24/7.

Mining and processing operations will require a lot of support. It would be a lot easier to provide that support with a colony on the Moon, including living spaces, food, maintenance, supply depots, recreation, social functions, etc, all of which would require a minimum population of a colony. That is not something that would be practical on an asteroid.
All these concerns have been addressed on this thread. (http://www.bautforum.com/life-space/65282-orbital-habitats-flexible-solution-humanity.html) The thread you're on now isn't about the technical feasibility of a space hab, but the psychological/biological aspects.

Reaching an asteroid, even if it passes close to the Earth, would require almost as much acceleration as going to Mars. Untrue. See my earlier post about NEOs and delta-v (change in acceleration).


There are other reasons.

Name 'em.

Noclevername
2007-Nov-16, 11:39 AM
We could mine the Moon with today’s technology.
Er, no. Who told you that whopper?


considering how relatively expensive and inherently fragile space stations will be, using them to smelt iron and extract aluminum would be prohibitively expensive. Wouldn't their fragility be dependent entirely on their design and construction? Nothing inherent about it. And building on the Moon would be no cheaper.



Those are the materials that will be needed most as we begin to build spacecraft in space instead of boosting them from Earth. The Moon would be a great place for that.
You keep saying that, but never say why. What makes the Moon "better"?


For materials mined on the Moon, there would be no delta V at all, because they would be processed right there. Also, there is a LARGE difference in mass between ore and finished product. Still have to ship it into orbit, which still means delta-v and a gravity well.


AFAIK, virtually all asteroids rotate, many in three axis, and some very rapidly. That would make solar collecting difficult.

Yes, just as the Moon has day and night, asteroids have day and night. And for either one, a solar-power sat in full sunlight can beam power to any shaded area.



Again, I was assuming this was something that would be done as we began moving out, not later on. Robot technology has advanced greatly, but even our best robots require a lot of care and a lot of supervision.
Probably both will occur at first.

The main advantage is that it would be quicker, easier, and cheaper to build a viable support colony on the Moon than on a space station.
?? Your basis for assuming this?

When they hit the Moon, those same materials are deposited there.

Widely scattered, and with most volatiles released and lost by the force and heat of impact.



Again, moving ore across those distances would not be very efficient.
For moving nonliving matter, distance is irrelevant. Only delta-v counts.

danscope
2007-Nov-16, 07:06 PM
Hi.....mental avenger..
EDIT: On re-reading I realize that last sentence is a bit unclear. What I mean is that supplying a Moonbase or a space habitat is equal in difficulty, and making a Moonbase or space habitat self-sufficient are equal in difficulty, not that they're all the same difficulty. Confused? I know I am.
*********
You do realize that there is a substancial gravity well for anything trying to boost off of the Moon? I think someone else mentioned this as well.
But let's not gloss over this enormous task . The LM was a light and fragile
piece of dedicated engineering for specific purpose. And it only brought back
a small sample of gravel for study. By contrast, getting to and from a space station is simpler by many degrees and all together practical by comparison to any activity on the moon. No question.
Dan

Noclevername
2007-Nov-16, 08:05 PM
Hi.....mental avenger..
EDIT: On re-reading I realize that last sentence is a bit unclear. What I mean is that supplying a Moonbase or a space habitat is equal in difficulty, and making a Moonbase or space habitat self-sufficient are equal in difficulty, not that they're all the same difficulty. Confused? I know I am.

That quote was from my post, not MentalAvenger's.


You do realize that there is a substancial gravity well for anything trying to boost off of the Moon? I think someone else mentioned this as well.
But let's not gloss over this enormous task . The LM was a light and fragile
piece of dedicated engineering for specific purpose. And it only brought back
a small sample of gravel for study. By contrast, getting to and from a space station is simpler by many degrees and all together practical by comparison to any activity on the moon. No question.
Da
When you factor in that a rotating space hab can provide 1g, over the as-yet-unkown effects of longterm low Lunar gravity, it looks even better. Partly balancing this out is the fact that a station needs to be fairly large to support rotation that won't induce vomiting (although that's based only on Earth-based centrifuge tests, rotation in space without Earth's gravity constantly shifting direction on you may not share this effect) while a supplied Moonbase could consist of a few linked cargo modules. However, a Moon station that small would not be self-sufficient and would require frequent resupply. A larger base, or a rotating space station, could be made more, but not fully (yet), self-sufficient through onboard plant growth. Either could support a crew who could use remote systems to mine and process materials.

MentalAvenger
2007-Nov-16, 09:21 PM
I was talking about the near future. Just what do you think is needed to pick up (quite possibly loose, or lightly held) material from an asteroid? Recently I was admonished (actually I was told the idea was absurd) for suggesting that an SUV sized rover could travel across the flat, open areas of Mars at 40mph. Now I am being told we currently have the robotic technology to go to an asteroid, mine the material, and bring it back. Ok.


I'm getting the feeling (actually, I've had it for a while now) that you're being contradictory just for the heck of it. Darned, you beat me to it. I was about to say the same about all y’all. :)


The only difference between the moon and an orbital station is that gravity is optional on an orbital station. Wow! You actually believe that? I’ll give you the chance to reread your comment and revise it.


And at the low end, it isn't. If you think that two thirds is almost the same you have a rather broad definition of the term.Nitpicking again? I’ll try to use more precise, accurate, and non-misunderstandable terminology in the future.


Assuming you're using it on the moon. I thought we were talking about use in Earth orbit. My concern, if it wasn't clear, was reducing the cost of maintenance and expansion of facilities in Earth orbit over the relatively near term (next few decades).And I was talking about overall expansion into space, using off-Earth materials.


For material returned from (for example) a carbonaceous asteroid, pretty much everything would be useful to a facility in orbit. Perhaps, if you have onboard facilities to process each of those materials. You’re talking about a lot of different, bulky, massive facilities and factories, all of which must be boosted into orbit from Earth. That would require a really BIG station. Recently I was (essentially) admonished for suggesting building a Station V type wheel space station a LOT smaller than the one you propose, with opponents pointing out how we can’t even afford to build the tinker-toy ISS.


At most, a rapid rotation would means you wouldn't attempt to aim the solar panels.Solar collectors would be cheaper and more efficient, but need to be aimed. Even solar panels need to be aimed to be effective.


. . . which can be done from Earth, just as we do with the two long lived Martian rovers. Requiring days to do simple little tasks.


Not if you are supporting facilities in orbit.It would eventually be cheaper and easier to build your Earth orbiting station with materials processed on the Moon, than boosting them from Earth, assuming we have a mining and processing colony there.


Do you have evidence of this? If the materials are in the asteroid, and it hits the Moon, they will be there. (except for volatiles) How could it be otherwise?

MentalAvenger
2007-Nov-16, 09:39 PM
All these concerns have been addressed on this thread. The thread you're on now isn't about the technical feasibility of a space hab, but the psychological/biological aspects. OK, let’s address those. One of the aspects of living in space will be dealing with the isolation. IMO, the best way to do that is to build a complete community, where the workers aren’t just there for a few months to work, but where they can live. Such a community requires living quarters for the workers, their families, and all the support groups. A mining and processing community would include workers, supervisors, warehousemen, cooks, cleaners, shop owners of all kinds, bartenders, musicians, and the families of everyone involved.

If you build a military base, all these services will spring up all around it. There is a good reason for that, and it is the same reason it would naturally occur on a Moon base. Such a base would require a lot of buildings, furnishings, and other materials. If the first constructions on the Moon were mining and processing plants, all the rest could be built right there with mostly local materials. In some cases, such as tunneling, no material is even needed for the living, storage, and manufacturing areas. For an orbital space station, ALL of the materials would have to be imported.

From a psychological standpoint, having a complete community makes sense. Of course, if you plan to ferry the hundreds of workers back to the Earth from orbit every few months, you could get by with a lot less. I wonder how much a round trip ticket from Florida to HEO would be……..

Noclevername
2007-Nov-16, 09:44 PM
Recently I was admonished (actually I was told the idea was absurd) for suggesting that an SUV sized rover could travel across the flat, open areas of Mars at 40mph. Now I am being told we currently have the robotic technology to go to an asteroid, mine the material, and bring it back. Ok.
Scooping up and returning a rubble-pile asteroid's material is a less complex task than delivering intact and maintaining for use a Mars-SUV

Darned, you beat me to it. I was about to say the same about all y’all. :)
It seems, based on your statements, that you haven't actually studied the technical details of asteroid mining and are just making assumptions about it. I recognize that this may be a false impression, if so can you please tell me what information you have on the subject?

Wow! You actually believe that? I’ll give you the chance to reread your comment and revise it.
In what way is his statement unbelieveable to you?

And I was talking about overall expansion into space, using off-Earth materials.
So was I.

Perhaps, if you have onboard facilities to process each of those materials. You’re talking about a lot of different, bulky, massive facilities and factories, all of which must be boosted into orbit from Earth. That would require a really BIG station. And how does this differ from shipping equipment to the Moon? Aside from the fact that it will need large landing rockets to reach the Lunar surface intact?

Recently I was (essentially) admonished for suggesting building a Station V type wheel space station a LOT smaller than the one you propose, with opponents pointing out how we can’t even afford to build the tinker-toy ISS.
Well, since we aren't those people, so what?

Solar collectors would be cheaper and more efficient, but need to be aimed. Even solar panels need to be aimed to be effective.
A rotating asteroid can be surrounded with panels relatively cheaply, providing power at all times. Not so for the Moon. Or a power satellite can be stationed in a parallel orbit to an asteroid, beaming power contiuously to the minesite. The Moonbase would require powersats to be in orbit, so it would require more of them (at minimum two, or more if their range is limited) to recieve the same amount of energy.
Requiring days to do simple little tasks.


It would eventually be cheaper and easier to build your Earth orbiting station with materials processed on the Moon, than boosting them from Earth, assuming we have a mining and processing colony there.
Same for an asteroid. And, methods developed to mine NEOs can be used on any asteroid or small moonlet, anywhere in the Solar System. Lunar mining processes are only useful on Luna (and possibly Mercury's night side, but you'd need to get the equipmment off the surface before sunrise.)

If the materials are in the asteroid, and it hits the Moon, they will be there. (except for volatiles) How could it be otherwise? Volatiles are the main reason to mine asteroids. We can't live in space without them, and they will be vital for making fuel as well.

Noclevername
2007-Nov-16, 09:48 PM
There is a good reason for that, and it is the same reason it would naturally occur on a Moon base. Such a base would require a lot of buildings, furnishings, and other materials. If the first constructions on the Moon were mining and processing plants, all the rest could be built right there with mostly local materials. In some cases, such as tunneling, no material is even needed for the living, storage, and manufacturing areas. For an orbital space station, ALL of the materials would have to be imported.


So (again) how exactly does this construction of a Moonbase differ from the construction of a space habitat using asteroidal materials? Aside from the fact that a Moonbase would have to import all its volatiles?

MentalAvenger
2007-Nov-16, 09:50 PM
Er, no. Who told you that whopper?Ok, why not, specifically?


Wouldn't their fragility be dependent entirely on their design and construction? Nothing inherent about it. I guess you missed the discussion on tethers, where it was pointed out that balancing, even on rigid wheel stations, would be critical, and how easy it would be for them to (essentially) self destruct.


And building on the Moon would be no cheaper. All materials for a space station must be mined somewhere, processed, and imported. On the Moon, a tunnel would provide shelter, living space, manufacturing space, etc.


You keep saying that, but never say why. What makes the Moon "better"? I have been explaining that.


Still have to ship it into orbit, which still means delta-v and a gravity well.A rather shallow gravity well. Without an atmosphere, materials could be launched into orbit with Mag-Lev rails.


Yes, just as the Moon has day and night, asteroids have day and night. And for either one, a solar-power sat in full sunlight can beam power to any shaded area.
Still waiting for someone to show that those will actually work or be practical.


?? Your basis for assuming this?Explained above.


Widely scattered, and with most volatiles released and lost by the force and heat of impact. True, volatiles will be lost. But the rest is still there. Though scattered about, there will concentrations of such, just as there are on Earth.


For moving nonliving matter, distance is irrelevant. Only delta-v counts. That’s what I meant (essentially).

Noclevername
2007-Nov-16, 10:14 PM
Ok, why not, specifically?.16 gravity, vacuum, two weeks of temperature extremes.


I guess you missed the discussion on tethers, where it was pointed out that balancing, even on rigid wheel stations, would be critical, and how easy it would be for them to (essentially) self destruct.
Well, no. The rotating section need not be the industrial section of the station, that's only needed for human habitation. Smaller centrifuges in the industrial side can provide any spin needed for processing materials.

All materials for a space station must be mined somewhere, processed, and imported. On the Moon, a tunnel would provide shelter, living space, manufacturing space, etc.
And digging tunnels requires large amounts of energy and is dangerous even on Earth. It would also need to be made airtight and insulated. It is not inhehrently any harder to make a livable tunnel that is to create a livable section of a space station.

I have been explaining that.
No, you've been asserting it. Your reasons why have so far not shown any inherent superiority over using near Earth asteroids.

A rather shallow gravity well. Without an atmosphere, materials could be launched into orbit with Mag-Lev rails.
Which would need to be built, powered and maintained.

Still waiting for someone to show that those will actually work or be practical.
http://en.wikipedia.org/wiki/Solar_power_satellite
Solar cells exist, microwave beam transmission of power exists. What problem do you have with the concept?


True, volatiles will be lost. But the rest is still there. Though scattered about, there will concentrations of such, just as there are on Earth.On Earth, there are much higher amounts, concentrated by dynamic forces; erosion, water seepage, tectonics, and biological activity. The moon is lacking those factors. And so you'd have to prospect over a vast area to find relatively small amounts of useful materials. And volatiles will still need to be imported.



That’s what I meant (essentially). Well, then what difference does distance make? If an NEO asteroid is easier to reach, easier to get back from, has a greater variety of useful materials, and has no noticeable gravity well, why do you keep saying the Moon is better?

Van Rijn
2007-Nov-16, 10:33 PM
Recently I was admonished (actually I was told the idea was absurd) for suggesting that an SUV sized rover could travel across the flat, open areas of Mars at 40mph. Now I am being told we currently have the robotic technology to go to an asteroid, mine the material, and bring it back. Ok.


You could build a huge rover, but there is no point. Forty MPH, however, would be a good way to get it destroyed. I'm not talking about anything like that, rather, just an expansion of sample return missions. Those go back to the '60s. And, this is something that could pay for itself, so there is a point to doing it.


Darned, you beat me to it. I was about to say the same about all y’all. :)


Which is telling. I have disagreements with Noclevername, JonClarke, IsaacKuo, and others occasionally, but the impression I have with you is that you disagree with just about everything everyone says.



Wow! You actually believe that? I’ll give you the chance to reread your comment and revise it.


I see no reason to revise it.



Perhaps, if you have onboard facilities to process each of those materials. You’re talking about a lot of different, bulky, massive facilities and factories, all of which must be boosted into orbit from Earth.


First, the equipment issue applies to the moon as well, with the added issue that it would have to be landed on the moon after being boosted into Earth orbit. Second, if the material comes from an asteroid, it makes no sense for processing facilities to be on the moon. However, orbital processing facilities could still use material shipped there for use from the moon. Third, initially, I wouldn't expect to have massive processing facilities, but limited facilities that make the most sense at the time. For instance, a fairly small processing station to extract water and other volatiles.



That would require a really BIG station. Recently I was (essentially) admonished for suggesting building a Station V type wheel space station a LOT smaller than the one you propose, with opponents pointing out how we can’t even afford to build the tinker-toy ISS.


See above. The size of the processing facilities would depend on what was needed. I'm far more interesting in early, small scale use of materials. Eventually, that would lead to larger stations.

By the way, my key point of disagreement in the previous discussion wasn't that you were suggesting a "Station V" design, but that you were insisting that it was the only valid choice for a rotating station. You seemed to have a very odd view about cables.

(skipping most of the rest)



If the materials are in the asteroid, and it hits the Moon, they will be there. (except for volatiles) How could it be otherwise?

Assuming we could find where there was an appropriate asteroid strike, it's virtually certain that there will be a loss of volatiles both on impact and over time. Much of the material would be scattered on impact as well. It is by no means clear that suitable mining locations will be found on the moon. I'm not saying it's impossible, but it certainly can't be assumed. On the other hand, we do know there are carbonaceous asteroids heavy with volatiles (in a pinch, we could always go to Phobos, which still has a delta V advantage).

Noclevername
2007-Nov-16, 10:40 PM
To sum it all up, there's nothing on the Moon we can't get elsewhere, and the Moon is sorely lacking in some things we can't do without.

Van Rijn
2007-Nov-16, 10:56 PM
To sum it all up, there's nothing on the Moon we can't get elsewhere, and the Moon is sorely lacking in some things we can't do without.

Yes. The key advantage of the moon is that getting there is relatively quick. The key disadvantages are that it lacks or has very little of some materials, and there are relatively high acceleration and energy requirements to reach its surface. I have no problem with the idea of lunar mining when appropriate. I do have a problem with the idea that this should be considered to the exclusion of all other options.

MentalAvenger
2007-Nov-17, 01:51 AM
It seems, based on your statements, that you haven't actually studied the technical details of asteroid mining and are just making assumptions about it. Is it time to start attacking the individuals qualifications, instead of sticking to addressing the facts and opinions?


.16 gravity, vacuum, two weeks of temperature extremes. Those are merely known conditions. That doesn’t explain why you think those factors are a problem.


Well, no. The rotating section need not be the industrial section of the station, that's only needed for human habitation. Smaller centrifuges in the industrial side can provide any spin needed for processing materials.Reality check. Have you ever visited a full blown steel mill? Have you any idea what is entailed in producing finished steel from ore, let alone finished steel products. Have you any idea of the mass, complexity, and sheer size of the operation? Do you have any idea what all it takes to smelt aluminum? The difference between spinning those thousands and thousands of tons up on a space station, and building them on the ground on the Moon IS the major difference that makes the Moon a far superior place for such an operation. Go visit a steel mill, then come and tell me about putting one on board a space station.


And digging tunnels requires large amounts of energy and is dangerous even on Earth. One NTBM could create a lot of tunnels in a relatively short time. On Earth, tunnels are often dangerous because they must go through certain areas. On the Moon, tunneling sites could be chosen for stability.


It would also need to be made airtight and insulated. An NTBM would leave essentially a glass lined tunnel behind.


It is not inhehrently any harder to make a livable tunnel that is to create a livable section of a space station. I suspect you meant “easier”?


No, you've been asserting it. Your reasons why have so far not shown any inherent superiority over using near Earth asteroids.I have been explaining it. I cannot help it if you don’t agree with my explanations. Your comment suggests it isn’t an “explanation” unless you agree with it. That is rather arrogant, IMO.


Which would need to be built, powered and maintained. Duh!! Of course it would. But it would also provide a very economical way to send finished materials to almost anywhere.


Solar cells exist, microwave beam transmission of power exists. What problem do you have with the concept?Frying anything nearby if the tracking system fails. In any case, if it was such a great system, we would be using it here on Earth. We are not.


On Earth, there are much higher amounts, concentrated by dynamic forces; erosion, water seepage, tectonics, and biological activity. The moon is lacking those factors. I give you that one.


Well, then what difference does distance make? The difference has been explained. I am visualizing a steel mill on a space station, and one on the Moon. No contest. Not only would such a station have to be incredibly huge, IMO it would be inherently dangerous. You couldn’t get me on one of those, not even for a stopover.

Noclevername
2007-Nov-17, 01:57 AM
I'm not knocking the Moon. It does have some good points, like lots of aluminum, iron, and oxygen, makes a convenient platform for telescopes both optical and radio (especially radio, as it blocks out Earth's blabbering) and it's dar pretty, besides.

One point in its favor is that, since our Glorious Leaders already plan to build a system to go back there, we might as well get some use out of it while we're there. But due to its low g, Luna will probably never be a place to live and raise a family. An industrial park, yes. A colonized home for humans, probably no. Or at least only on a very limited scale, especially if the effects of long-term low-g turn out to be as detrimental as extended zero-g. Doubtless someone will be crazy... I mean adventurous enough to try spending a lifetime on the Moon and maybe even having children there. But my guess is, once those kids start to grow up with bone, digestive, and circulatory problems, the number of Selenite immigrants will drop off sharply.

MentalAvenger
2007-Nov-17, 02:14 AM
You could build a huge rover, but there is no point. Forty MPH, however, would be a good way to get it destroyed. The point wasn’t whether it was a practical rover, but rather whether it could travel over flat, level terrain at 40mph in .38 gravity. IMO, that would be a LOT easier job for a rover than traveling to an asteroid, catching up to it, matching its spin, landing on it, digging up significant amounts of useful ore, taking off again, and transporting it to a space station in orbit. I am quite confident I could do the former with current equipment. I wouldn’t even try the latter with current equipment.


Which is telling. I have disagreements with Noclevername, JonClarke, IsaacKuo, and others occasionally, but the impression I have with you is that you disagree with just about everything everyone says. Perhaps you would prefer a discussion only with people who agree with your every opinion. Maybe some of my ideas are radical. Maybe some of them are unusual. And maybe some of my ideas are different than almost anyone else. But, in my considerable experience in a dozen different fields of endeavor, most of them would be a better way to perform some of the tasks presented. I don’t disagree to be disagreeable. I disagree because I have a different opinion. Perhaps I am impatient with the slow (or non-existent) progress in space exploration, but that is because I see so much waste, timidity, and lack of vision.

You might notice that many of my suggestions include rather brute force, or at least very large and concerted efforts, as a way to accomplish the steps needed for space exploration. That is because, IMO, small baby steps, with two steps forward and one back, are a criminal waste of both time and resources. We went to the Moon because we went hell bent for leather. We could do the same now. But everyone is so afraid of a small failure, they are afraid to try anything anymore. A turtle never made any progress without sticking its neck out. As long as we stay safely in our shell, we will be safe, but we won’t get anywhere.


I see no reason to revise it. You see no difference between the Moon and a space station? OK.


First, the equipment issue applies to the moon as well, with the added issue that it would have to be landed on the moon after being boosted into Earth orbit. IMO, the amount of actual material needed to build a plant on the Moon, compared to the amount of material required to build the same plant on a space station (which would, of course, include addition space station structural elements to support the plant section) is significant. It might require as much as twice as much imported material for a plant on a space station, possibly more.


Second, if the material comes from an asteroid, it makes no sense for processing facilities to be on the moon. Strawman. No one that I know of has ever suggested that.


See above. The size of the processing facilities would depend on what was needed. I'm far more interesting in early, small scale use of materials. Eventually, that would lead to larger stations.IMO, the same amount of materials and the same amount of effort overall could produce a much larger facility, with a much greater capacity, on the Moon.


By the way, my key point of disagreement in the previous discussion wasn't that you were suggesting a "Station V" design, but that you were insisting that it was the only valid choice for a rotating station. You seemed to have a very odd view about cables.Thank you for the explanation. IMO, living on a rotating structure would be dangerous enough without the added complications of a tether design. Everything from docking to moving around to balancing would be easier and safer in a Station V type. IMO.

Safety in space is going to be one of the most costly, time consuming, and critical elements. I believe in reducing the risks as much as possible when practical.


Assuming we could find where there was an appropriate asteroid strike, it's virtually certain that there will be a loss of volatiles both on impact and over time. Much of the material would be scattered on impact as well. It is by no means clear that suitable mining locations will be found on the moon. Granted.

Noclevername
2007-Nov-17, 02:16 AM
Is it time to start attacking the individuals qualifications, instead of sticking to addressing the facts and opinions?Sorry if I offend. I just find your statements about asteroid mining appear to reflect a point of view that doesn't match any of the proposed methods I've heard or read about.


Those are merely known conditions. That doesn’t explain why you think those factors are a problem.
Aside from the gravity, they're the exact same conditions you'd find near or on an asteroid, or in Earth orbit. And as I said, a simple centrifuge can solve that. So why do you seem to think it's any easier to do the exact same thing on the Moon as in a space facility?


Reality check. Have you ever visited a full blown steel mill? Have you any idea what is entailed in producing finished steel from ore, let alone finished steel products. Have you any idea of the mass, complexity, and sheer size of the operation? Do you have any idea what all it takes to smelt aluminum? The difference between spinning those thousands and thousands of tons up on a space station, and building them on the ground on the Moon IS the major difference that makes the Moon a far superior place for such an operation. Go visit a steel mill, then come and tell me about putting one on board a space station.

I have, I do, and I am. A space-based facility-- or a Moon-based one-- will be designed for the environment in which its built. No particular reason it can't be done on a smaller or larger scale in space.




One NTBM could create a lot of tunnels in a relatively short time. On Earth, tunnels are often dangerous because they must go through certain areas. On the Moon, tunneling sites could be chosen for stability.
An NTBM would leave essentially a glass lined tunnel behind.

And an NMTB is...? Let me guess. It's presently nonexistent spec-tech like an orbital elevator or self-replicating nanobots?


I suspect you meant “easier”?
It will initially be about the same level of difficulty. As time passes and mass-production becomes possible in space, it will become far easier to build a section of space station living area that it would be to build the same volume of livable tunnel.


I have been explaining it. I cannot help it if you don’t agree with my explanations. Your comment suggests it isn’t an “explanation” unless you agree with it. That is rather arrogant, IMO.
No, your statements thus far have indicated that you are, or appear to be, misinformed on a number of key matters. My comment suggests only that you are repeating things as truisms without fully researching their accuracy.



Duh!! Now who's acting arrogant?



Of course it would. But it would also provide a very economical way to send finished materials to almost anywhere.
As would a spacecraft fully fueled with asteroidal volatiles.

Frying anything nearby if the tracking system fails. In any case, if it was such a great system, we would be using it here on Earth. We are not.


It's not needed on Earth, as we have cables. And no, the experiments done have shown that even high-powered beams of the frequencies and densities proposed would not "fry" anyone. That's a science-fictional scenario, not a scientific one. Automatic negative-feedback safety cutoffs are a simple matter to design into the system in any case.




[=The difference has been explained. I am visualizing a steel mill on a space station, and one on the Moon. No contest. Not only would such a station have to be incredibly huge, IMO it would be inherently dangerous. You couldn’t get me on one of those, not even for a stopover.

What you are visualizing, and what the practical design actually will be like, may or may not bear any relation. If you don't want to go, that's fine, no one's forcing you. There are also people who refuse to fly because the wings might fall off, or refuse to climb hills because lightning might strike them. A properly designed indudtrial facility-- on Earth, the Moon, or in space --will be as safe as those designing and working on it can make it.

MentalAvenger
2007-Nov-17, 02:25 AM
I'm not knocking the Moon. It does have some good points, like lots of aluminum, iron, and oxygen, makes a convenient platform for telescopes both optical and radio (especially radio, as it blocks out Earth's blabbering) and it's dar pretty, besides. Agreed. That has always been one of my main points.


But due to its low g, Luna will probably never be a place to live and raise a family. An industrial park, yes. A colonized home for humans, probably no. Or at least only on a very limited scale, especially if the effects of long-term low-g turn out to be as detrimental as extended zero-g. As noted in the Mars threads, I almost agree. It will be some time before we know the answer to that one. IMO, it is likely that .38 G will be sufficient to remain healthy over the long term. I Have my doubts about 1/6th G. But I think it is possible that 1/6th G may be all that is required for healthy humans for extended periods of time. That is something that a Station V type station could have told us by now if we had built one, instead of the nearly useless ISS.


But my guess is, once those kids start to grow up with bone, digestive, and circulatory problems, the number of Selenite immigrants will drop off sharply. We have to wait to see.

Noclevername
2007-Nov-17, 02:26 AM
You might notice that many of my suggestions include rather brute force, or at least very large and concerted efforts, as a way to accomplish the steps needed for space exploration. That is because, IMO, small baby steps, with two steps forward and one back, are a criminal waste of both time and resources. We went to the Moon because we went hell bent for leather. We could do the same now.

Now that's the first thing you've said that I agree 100% with. We should be doing as much as we can, not wasting our potential.

MentalAvenger
2007-Nov-17, 02:49 AM
Sorry if I offend. I just find your statements about asteroid mining appear to reflect a point of view that doesn't match any of the proposed methods I've heard or read about.No problem. I just disagree with some of the estimates.


Aside from the gravity, they're the exact same conditions you'd find near or on an asteroid, or in Earth orbit. Not really. Having a solid, base to build upon, that doesn’t need to be balanced, and doesn’t care how massive the equipment is, IMO is all the difference in the world (or in the Moon) :)


I have, I do, and I am. A space-based facility-- or a Moon-based one-- will be designed for the environment in which its built. No particular reason it can't be done on a smaller or larger scale in space.The main difference, as noted, is the base upon which it is all built. Every facility on a rotating space station will require virtually an equal amount of basic station structure to build upon. On the Moon, the surface (or the tunnel) is already there.


And an NMTB is...? Let me guess. It's presently nonexistent spec-tech like an orbital elevator or self-replicating nanobots? The Air Force had a Nuclear Tunnel Boring Machine in operation in the southwestern US 30 years ago. That is how they built that underground labyrinth of tunnels down there. Somewhere I have all the information on that, including photos of the NTBM.


It will initially be about the same level of difficulty. As time passes and mass-production becomes possible in space, it will become far easier to build a section of space station living area that it would be to build the same volume of livable tunnel. I will have to respectfully disagree. I have built a lot of buildings, rooms, and other constructions. IMO, it would be a lot more costly and difficult to build the same living space aboard a space station.


No, your statements thus far have indicated that you are, or appear to be, misinformed on a number of key matters. My comment suggests only that you are repeating things as truisms without fully researching their accuracy. They are called opinions, based on a great deal of experience in many different fields.


As would a spacecraft fully fueled with asteroidal volatiles.Ignoring, of course, the added problems of refining those volatiles insitu.


And no, the experiments done have shown that even high-powered beams of the frequencies and densities proposed would not "fry" anyone. Please don’t attempt to tell me that. I worked on high powered radars for 4 years. I understand high powered radar very well.


What you are visualizing, and what the practical design actually will be like, may or may not bear any relation. There are certain physical aspects of a steel mill that cannot be changed. Working with large amounts of ore, molten steel, and the massive machinery required to process it is a fact. Unless you know of a way to avoid those incredibly massive Bessemer Converters, furnaces, rolling mills, etc., etc., etc., the sheer mass and heat IS a major problem. And if you know of an alternative method, I am sure you could become an instant billionaire by sharing those secrets with the relevant people in the steel industry.

MentalAvenger
2007-Nov-17, 02:50 AM
BTW, believe it or not, I have a potential social life waiting for me. It’s Friday night, and I am going out dancing. Its been fun. Caio.

Noclevername
2007-Nov-17, 03:05 AM
No problem. I just disagree with some of the estimates. That's fine. Time will tell what's really feasible, right now all we have are opinions.


Not really. Having a solid, base to build upon, that doesn’t need to be balanced, and doesn’t care how massive the equipment is, IMO is all the difference in the world (or in the Moon) :)
A nonrotating section of a space station doesn't care either. As I said, only the living quarters need spin.

The main difference, as noted, is the base upon which it is all built. Every facility on a rotating space station will require virtually an equal amount of basic station structure to build upon. On the Moon, the surface (or the tunnel) is already there.
No, the tunnels will need to be dug. The surface will still need to be prepared, industrial machinery won't be resting directly on loose native regolith. So just as with a space station, building materials and energy will be needed.

The Air Force had a Nuclear Tunnel Boring Machine in operation in the southwestern US 30 years ago. That is how they built that underground labyrinth of tunnels down there. Somewhere I have all the information on that, including photos of the NTBM.
OK, post them if you find them. I'd like to know in particular how much it masses.

I will have to respectfully disagree. I have built a lot of buildings, rooms, and other constructions. IMO, it would be a lot more costly and difficult to build the same living space aboard a space station.
Please describe why.

Ignoring, of course, the added problems of refining those volatiles insitu.
No, taking it into account, actually.

Please don’t attempt to tell me that. I worked on high powered radars for 4 years. I understand high powered radar very well.
Then why did you say you did not know about microwave power transmission?



There are certain physical aspects of a steel mill that cannot be changed. Working with large amounts of ore, molten steel, and the massive machinery required to process it is a fact. Unless you know of a way to avoid those incredibly massive Bessemer Converters, furnaces, rolling mills, etc., etc., etc., the sheer mass and heat IS a major problem. And if you know of an alternative method, I am sure you could become an instant billionaire by sharing those secrets with the relevant people in the steel industry.
Yes, as I said, that's using current mass-production techniques designed to be used on Earth, under Earth conditions. Space processes will need to start small and gradually bootstrap no matter where the foundries and factories are located; that's a limitation imposed by Earth's gravity, not by the destination of said foundries and factories. Small-scale space production, possibly using simple solar furnaces, will start the first steps, and the infrastructure will be built from there. The Moon offers no greater benefits of heat dispersal, or size of equipment; in zero-g, there are no size or weight limits.

danscope
2007-Nov-17, 05:26 AM
Oh...by the way: Tunnel boring machines are extremly heavy, complex, and require water to cool the face mill, as well as a system to remove the loose material and a very large crew to run it. The suggestion of utilizing this in space
borders on the super fantastic, In my opinion. I don't see anything like this happening any time soon or in the distant future. But....you can dream.
Best regards, Dan

MentalAvenger
2007-Nov-17, 09:20 AM
A nonrotating section of a space station doesn't care either. As I said, only the living quarters need spin.All the processes I have seen in making steel and aluminum rely heavily upon gravity. Due to the processes involved, I’d think that trying that in zero-G would be extremely difficult. However, I can see how 1/6th G might have some advantages.


No, the tunnels will need to be dug. The surface will still need to be prepared, industrial machinery won't be resting directly on loose native regolith. So just as with a space station, building materials and energy will be needed.But, IMO, not nearly as much on the Moon, since some of the material used will be right there.


Please describe why. If you don’t understand why, I might not be able to explain it. But later, when I have more time, I might try.


Then why did you say you did not know about microwave power transmission? I didn’t.


Yes, as I said, that's using current mass-production techniques designed to be used on Earth, under Earth conditions. Space processes will need to start small and gradually bootstrap no matter where the foundries and factories are located;
There is a major difference between 1/6th gravity and zero-G. Processes that currently require gravity will probably still work in less gravity, but certainly not in zero gravity. Earlier you were using the gravity of the Moon to illustrate a difficulty, now you seem to be dismissing it.


Small-scale space production, possibly using simple solar furnaces, will start the first steps, and the infrastructure will be built from there. And that is one of the problems. As always, small scale productions, especially of something like steel and aluminum, are very inefficient compared to larger scale productions.


The Moon offers no greater benefits of heat dispersal, or size of equipment Heat can be exchanged with the underground mass of material on the Moon, in both directions. That is a big advantage.

Noclevername
2007-Nov-17, 05:31 PM
All the processes I have seen in making steel and aluminum rely heavily upon gravity. Due to the processes involved, I’d think that trying that in zero-G would be extremely difficult. However, I can see how 1/6th G might have some advantages.
Now you're repeating your truisms. So let me repeat one-- in zero-g, spin can provide any amount of gravity. A cetrifuge is long-proven technology.

But, IMO, not nearly as much on the Moon, since some of the material used will be right there.
Just as it would be on an asteroid.

If you don’t understand why, I might not be able to explain it. But later, when I have more time, I might try.
Okay.

I didn’t.
I may have misinterpreted what you wrote. Were you using the 1975 test results?


There is a major difference between 1/6th gravity and zero-G. Processes that currently require gravity will probably still work in less gravity, but certainly not in zero gravity. Centrifuge. Adjustable. Again.



Earlier you were using the gravity of the Moon to illustrate a difficulty, now you seem to be dismissing it.

The Moon's gravity is not adjustable. You're stuck with it. And it may not be ideal for the processes you described.

And that is one of the problems. As always, small scale productions, especially of something like steel and aluminum, are very inefficient compared to larger scale productions.

And would be on the Moon, too. The problem is the expense of shipping the initial equipment. Once there, as long as you're more efficient than getting the same materials form Earth, anything above that is a bonus.

Heat can be exchanged with the underground mass of material on the Moon, in both directions. That is a big advantage. Not that big. In zero-g, and arbitrarily large shaded radiator can be built. An alternate method, since an asteroid mine will probably be cracking volatiles anyway, is to use the unneeded components as a cooling exhaust. Let them carry excess heat into space and disperse.

MentalAvenger
2007-Nov-18, 02:21 AM
Ok, let me use an example. These are arbitrary figures, but I’ll try to keep it all in scale. We are starting form scratch, no structures are yet in place. We’ll make two steel mills, one on a rotating station, and one on the Moon. I’ll start small. Let’s say the entire mill weighs 1000 tons (on Earth). That’s just the equipment without any buildings or support structures. I am also assuming all the equipment must be adjacent because of the nature of the steel mill, transferring molten metal down the line etc.

Space station:
In order to support 1000 tons of mass as a centrifuge, I estimate that the total amount of structure (minimum) would be about 2000 tons. That includes the enclosure for the mill equipment, and all the structures needed to support it safely as it swings about a central hub. Of course, to balance the centrifuge, you’ll need another 1000 tons, supported by another 2000 ton structure. Now it is all in balance.

Moon:
Set up the equipment on bedrock, outside. Savings: 5000 tons of structure. A lightweight enclosure can be erected around the equipment, but since air interferes with some processes anyhow, it probably isn’t necessary, except as a sunshade.

Space station:
When your asteroid ore carriers arrive, you have to either despin the steel mill, or figure out how to get all that mass out to the end of the centrifuge. Unless you want to run a single batch at a time (very inefficient), despinning with all that molten metal might not be either easy or safe. Also, all that mass will have to be balanced on the other side of the centrifuge.

Moon:
The ore haulers dump their load and leave for more. No interruptions in the schedule. Also, no time or energy involved in balancing those large amounts of mass.

Space station:
As the steel processing proceeds, large amounts of mass will be moving along the line, requiring constant balancing of the loads.

Moon:
The steel moves down the line, no problem.

Space station:
Finished product has to be removed from the steel mill. Not easy since it is spinning. And, again, balancing large amounts of mass will not just be required, but critical.

Moon:
Back up the trucks and load them with finished steel.

Noclevername
2007-Nov-18, 02:26 AM
I’ll start small. Let’s say the entire mill weighs 1000 tons (on Earth).

Is that even remotely realistic for a first step? Anywhere off Earth? We have to cut the coat to fit the cloth.

Start much smaller. Like processing rigs that have been tested for use in space already.

danscope
2007-Nov-18, 04:31 AM
He continues to ignore the fact that there is no way to boost the product off the Moon which he is so fond of.This is where his scheme crashes to the ground.
I suppose that he wishes to boost his product off the moon's surface and into moon orbit with "Spring Steel " .
Dear Sir: There are some considerable problems with the Moon Mining and Manufacturing scheme. Feasability comes to mind.
Dan

Noclevername
2007-Nov-18, 04:34 AM
He continues to ignore the fact that there is no way to boost the product off the Moon which he is so fond of.This is where his scheme crashes to the ground.
I suppose that he wishes to boost his product off the moon's surface and into moon orbit with "Spring Steel " .
Dear Sir: There are some considerable problems with the Moon Mining and Manufacturing scheme. Feasability comes to mind.
Dan

Actually, the Lunar mag-launcher scenario he mentioned is fairly realistic as a long-term goal. But certainly not a first step, or even a tenth. It'll have to wait until the Moon has an established industrial infrastructure and a sizeable power plant.

Van Rijn
2007-Nov-18, 05:07 AM
Ok, let me use an example. These are arbitrary figures, but I’ll try to keep it all in scale. We are starting form scratch, no structures are yet in place. We’ll make two steel mills, one on a rotating station, and one on the Moon. I’ll start small. Let’s say the entire mill weighs 1000 tons (on Earth).


That's small? You are either imagining a completely different scale than we are, or you are deliberately picking extreme numbers. I'm interested in materials to expand and supply space stations: Perhaps a hundred pounds or so for a system to extract water from carbonaceous material, a few hundred pounds for hardware to process a limited amount of aluminum from other material, etc.

I doubt they would even bother with iron, but obviously anything there would be designed for the purpose, not mass production on Earth.

Yeesh.

MentalAvenger
2007-Nov-18, 06:57 AM
Is that even remotely realistic for a first step? Anywhere off Earth? We have to cut the coat to fit the cloth. I was starting small. After all, we were talking about processing the results of asteroid mining. In order to make such mining even halfway practical, you’d have to be able to process the ore brought back from the asteroids. It wouldn’t be practical to send a spacecraft on a 2 year journey, expending considerable amounts of fuel, and utilizing a billion dollar craft, to bring back 200 pounds of ore. A 1000 ton steel mill would be a very small mill. And I did use the same specs for both places, the space station and the Moon.

MentalAvenger
2007-Nov-18, 07:05 AM
He continues to ignore the fact that there is no way to boost the product off the Moon which he is so fond of.This is where his scheme crashes to the ground.You apparently missed the post that suggested Mag-Lev rail launch. Even just an electric rail launch would work. It would be simple, straightforward, economical, and reliable. With no atmosphere (essentially), velocity would not be a problem, as it would be on Earth. Once the rail is built, anything can be sent into lunar orbit or beyond easily and inexpensively. Of course it has to be built first, but so does each and every other component we have been talking about.

BTW, do you have anything positive to contribute, or will you continue to simply snipe at my comments with nothing more than (sometimes incorrect) criticisms? Just wondering.

MentalAvenger
2007-Nov-18, 07:14 AM
That's small? You are either imagining a completely different scale than we are, or you are deliberately picking extreme numbers. As noted above, I was trying to keep in context with the current direction of this discussion, asteroid mining vs Moon mining.


I'm interested in materials to expand and supply space stations: Perhaps a hundred pounds or so for a system to extract water from carbonaceous material, a few hundred pounds for hardware to process a limited amount of aluminum from other material, etc.That would hardly make a trip by a dedicated spacecraft to an asteroid, and back, worthwhile.

Perhaps this was our misunderstanding regarding robotic asteroid miners. I envisioned practical mining operations with some chance of eventually paying for themselves. You appear to be talking about little more than a sample return mission which would fall orders of magnitude short of paying for itself.


I doubt they would even bother with iron, but obviously anything there would be designed for the purpose, not mass production on Earth. That was merely an example. OK, make it aluminum instead. Similar masses of equipment, a lot more energy required. Whatever. The point was, one to one between the same mill on the Moon, or on a space station, the Moon wins hands down. That is, of course, if we are talking about practical industrial application, not merely experimentation.

Van Rijn
2007-Nov-18, 08:15 AM
Perhaps this was our misunderstanding regarding robotic asteroid miners. I envisioned practical mining operations with some chance of eventually paying for themselves. You appear to be talking about little more than a sample return mission which would fall orders of magnitude short of paying for itself.


Uhm, no. I'm just not assuming ridiculous mass requirements, but actually considering hardware designed for the purpose. For instance, to extract water from water-containing minerals from an asteroid, using a low mass reflector heating a chamber that is fed dust with an Archimedes screw.




That was merely an example. OK, make it aluminum instead. Similar masses of equipment, a lot more energy required. Whatever. The point was, one to one between the same mill on the Moon, or on a space station, the Moon wins hands down. That is, of course, if we are talking about practical industrial application, not merely experimentation.

The point is that you are only interested in the moon, so you'll make all sorts of poorly backed assertions to support that. Of course, that's typical of your posts. I know you don't like to hear it, but if several people are telling you that you need to research things a bit more before making all these assertions, you might want to think about doing it.

Noclevername
2007-Nov-18, 03:45 PM
I was starting small.
But not realistically small.


After all, we were talking about processing the results of asteroid mining. In order to make such mining even halfway practical,
Define practical.



you’d have to be able to process the ore brought back from the asteroids. It wouldn’t be practical
Again, why not?


to send a spacecraft on a 2 year journey, expending considerable amounts of fuel, (bold mine)

Distance does not equal fuel consumption. You do still remember what was said about NEOs with less delta-v that a Moon shot, don't you?




and utilizing a billion dollar craft,
So use a cheaper one.


to bring back 200 pounds of ore.

Unless that's all you need. If not, bring back more.



A 1000 ton steel mill would be a very small mill.
Not if it's got to be lifted from Earth.

Nor is steel a necessary component for most proposed plans for space-based manufactured structures.


And I did use the same specs for both places, the space station and the Moon.

And made a lot of WAGs about what will take place there. Did you actually research the numerous proposed methods of either asteroid or Lunar mining and materials extraction that have been around since the early 1970s?

danscope
2007-Nov-18, 07:03 PM
You apparently missed the post that suggested Mag-Lev rail launch. Even just an electric rail launch would work. It would be simple, straightforward, economical, and reliable. With no atmosphere (essentially), velocity would not be a problem, as it would be on Earth. Once the rail is built, anything can be sent into lunar orbit or beyond easily and inexpensively. Of course it has to be built first, but so does each and every other component we have been talking about.

BTW, do you have anything positive to contribute, or will you continue to simply snipe at my comments with nothing more than (sometimes incorrect) criticisms? Just wondering.

Hi, A scrutiny of your schemes for the industrialization of the moon is bound to happen when you post on a forum such as this.
As far as my contributions are concerned, I have limited myself to exploring the
advantages and practicality of the 2001 space odysee design, of which I find much to reccomend , and have offered a number of solutions to potential problems with such design such as boosting the components necessary for
it's construction, and the convenient balancing of such a structure as well as the practical assembly of this design.
Having said what I have in reference to your scheme for the mass
manufacture of everything from 6-32 machine screws to submarine pressure hulll at no cost on the surface of the moon for fun and profit, I shall be silent.
Why no let your work and dreams speak for themselves? Fair enough.
I wish you joy of such invention. I'll leave it to others to " Point out the holes . It should be a shared experience after all.

Good luck with your scheme.
Dan

Noclevername
2007-Nov-18, 10:38 PM
Perhaps this was our misunderstanding regarding robotic asteroid miners. I envisioned practical mining operations with some chance of eventually paying for themselves. You appear to be talking about little more than a sample return mission which would fall orders of magnitude short of paying for itself.
The first trip is never going to pay for itself. Nor is the second, third or tenth. The early steps of ET bootstrapping are always going to be slow, no matter what the location. Do some research. Learn the proposals-- O'Neill's, John Lewis', etc. Examine the technical details of the extraction methods and plans adapted to work in space. Don't try to just put an Earth steel mill on the Moon or in orbit. Start with what can actually be done.

MentalAvenger
2007-Nov-19, 03:44 AM
Uhm, no. I'm just not assuming ridiculous mass requirements, but actually considering hardware designed for the purpose. Nothing ridiculous about the mass estimates I used in my example. I used the same mass for both the space station and the Moon in order to make a direct comparison. I was merely responding to assertions that asteroid mining and centrifuge space station processing is better than mining and processing on the Moon. That is all.


For instance, to extract water from water-containing minerals from an asteroid, using a low mass reflector heating a chamber that is fed dust with an Archimedes screw. I was using steel (or aluminum) as one example. After all, one of the benefits of mining, whether it is on asteroids or the Moon, is to provide materials to build spacecraft in space, without boosting those very massive materials up from Earth. Virtually the entire structure of a spacecraft will be aluminum, steel, and various alloys of both. Those are the materials which, when produced in space (or on the Moon), will provide the greatest savings and therefore the best ROI.


The point is that you are only interested in the moon, so you'll make all sorts of poorly backed assertions to support that. That statement is false. I was one of the first persons here (recently) to advocate a Station V type rotating station instead of the white elephant ISS. Such a station, in orbit around the Earth and/or the Moon, would be virtually a necessity for long term interplanetary exploration and settlement. Such a station would perform many vital functions, and provide many important services. I just don’t think that refining ore into finished goods is one of them.


Of course, that's typical of your posts. Hmmmmm…….back to attacking the poster, instead of addressing the issues. Whatever.


I know you don't like to hear it, but if several people are telling you that you need to research things a bit more before making all these assertions, you might want to think about doing it.Actually I depend upon such feedback. Just because I don’t happen to agree, does not mean I don’t take each piece of advice under consideration. Whether or not it is obvious, I really appreciate the time and effort each of you puts into discussing these issues with me. I hope you do the same. In any case, IMO, many of the criticisms have more to do with misunderstanding context, than they do with actual differences of opinion.

MentalAvenger
2007-Nov-19, 04:08 AM
But not realistically small.Obviously another misunderstanding. I was not attempting to demonstrate what scale we should use to begin such ventures in space. I only meant that I was starting small with my example. This would be perhaps a processing plant that would be in operation in, say, 20 years. It was intended only as an example of the difference in complexity and practicality between a centrifuge plant and a planet based plant. It had nothing to do with the scale of start-up projects.


Define practical. Money, ROI. If such operations are to pay for themselves, they have to operate on a scale that utilizes the equipment and manpower in a manner that realizes a profit. In my example, the profit would lie in making spacecraft structural components cheaper than they can be boosted up from Earth.


Again, why not? I won’t dignify your out-of-context incomplete-sections-from-two-different-sentences comment with a relevant response.


Distance does not equal fuel consumption. You do still remember what was said about NEOs with less delta-v that a Moon shot, don't you?Expending considerable amounts of fuel to move both the robotic spacecraft and the ore it is carrying. I wasn’t making a delta-V comparison here, only pointing out the need to move the ore.


So use a cheaper one.Irrelevant nit-picking. You pick a figure you think your robotic miner/hauler would cost. We’ll use your figures.


Unless that's all you need. If not, bring back more. If you only bring back 200 pounds of steel or aluminum ore (which is what I was referring to), it wouldn’t be worth the trip.


Not if it's got to be lifted from Earth.


Nor is steel a necessary component for most proposed plans for space-based manufactured structures.As noted earlier, let’s make it aluminum instead. That would probably be THE major component in building interplanetary spacecraft.


And made a lot of WAGs about what will take place there. I used the same figures to make the station/Moon comparison equal. Use any figures you want(for a production mill, not a test setup), make the two equal, and the relative comparison will remain the same.


Did you actually research the numerous proposed methods of either asteroid or Lunar mining and materials extraction that have been around since the early 1970s? Long ago, in a forum far far away, all that was gone over in excruciating detail. The bottom line remains the same.

MentalAvenger
2007-Nov-19, 04:13 AM
Hi, A scrutiny of your schemes for the industrialization of the moon is bound to happen when you post on a forum such as this. Generally, I don’t advocate developing the Moon in this manner. This was merely in comparison between attempting to produce finished metal products from ore on a space station, or on the Moon.


Having said what I have in reference to your scheme for the mass
manufacture of everything from 6-32 machine screws to submarine pressure hulll at no cost on the surface of the moon for fun and profit, I shall be silent.Beautiful Strawman. Since I have never advocated anything of the sort, your comment is actually irrelevant.

It would be helpful if y’all would try to keep these things in context.

MentalAvenger
2007-Nov-19, 04:26 AM
The first trip is never going to pay for itself. Nor is the second, third or tenth. The early steps of ET bootstrapping are always going to be slow, no matter what the location. My examples had nothing to do with baby-steps, ramping up, working up to full speed, or anything even remotely related to that issue. That is an entirely different discussion. As stated, my examples were intended only as a direct and equal comparison between two very different sites for the same process.


Do some research. Learn the proposals-- O'Neill's, John Lewis', etc. Examine the technical details of the extraction methods and plans adapted to work in space. You aren’t listening…………..


Don't try to just put an Earth steel mill on the Moon or in orbit. Start with what can actually be done.One last time, neither my comments nor my examples were intended to suggest, insinuate, allude to, or advocate start-up, current-capability, first-try, experimental-set-up, or anything like that at all. It was a direct comparison between the problems and advantages between the SAME setup on a rotating space station or on the Moon. You asked, I responded.

If you want to discuss the best way to start such processes, please start a discussion and I will participate. This discussion was supposed to be about Evolutionary Psychology and Physiology. I actually addressed that earlier, and the comments were ignored.

Noclevername
2007-Nov-19, 03:54 PM
My examples had nothing to do with baby-steps, ramping up, working up to full speed, or anything even remotely related to that issue. That is an entirely different discussion. As stated, my examples were intended only as a direct and equal comparison between two very different sites for the same process.
A process which is totally different than anything that will actually be used in space. You might as well have used hand-pumped bellows and a coal fired forge for all the relevance it has.

Why the heck should you want to "argue" useless abstracts instead of a practical, realistic scenario? Try again with something that's actually plausible.





You aren’t listening…………..
You aren't saying anything remotely signifigant to your topic of choice.

Say something plausible about it and I'll listen. Until then you're just wasting space.


This discussion was supposed to be about Evolutionary Psychology and Physiology. I actually addressed that earlier, and the comments were ignored.Oh, now, after two and a half pages, you want to go back to the OP? You are the one who keeps coming back to this thread with assertions about the "superiority" of Lunar mining. Then you gave us an irrelevant fantasy about 1000 ton steel mills using exclusively Earth-adapted technology. You ignore any suggestion to research practical solutions. Now, suddenly, you're complaining that I'm off-topic. :wall:

Forget it, this horse is dead, and the beating is getting tiring.

MentalAvenger
2007-Nov-20, 12:10 AM
A process which is totally different than anything that will actually be used in space. You might as well have used hand-pumped bellows and a coal fired forge for all the relevance it has. You seem determined to find a way to misunderstand what I posted, even though I have explained it in painstaking detail. I will try once more. My comparison was NOT about the process itself. I was making a comparison (http://www.onelook.com/?w=comparison&ls=a). 1000 tons too much? Use 100 tons, or 50 tons, or 20 tons. You don’t like the process? Use any process you want. Use the latest process available. Use the processes that have been proposed by your heroes. Hell, use a process that hasn’t even been thought of yet. It doesn’t matter. The POINT was, the difference between a process installed on a rotating centrifuge space station, and the SAME process installed on a planetary surface, in this case the Moon. YOU are the one who asked me to explain. I did.

As I pointed out earlier, the only criteria is that it be a processing plant capable of processing a significant amount of ore. Don’t go ballistic, I’ll explain “significant”. As discussed in other threads, one of the main reasons to process metals off-Earth is so that those heavy, bulky materials do not have to be boosted out of Earth’s gravity well (http://en.wikipedia.org/wiki/Gravity_well). The use of those metals would be to build spacecraft for missions to Mars and other planets. As many others have pointed out, in order to make the procedure economically feasible, there would have to be certain volume of use of materials. The larger the volume, the more economical. I am assuming, for the purposes of this example, producing a half dozen spacecraft per year in space. The example assumed a plant capable of producing metals in amounts sufficient to fill this need. Producing aluminum in 100 pound lots would not be practical for this purpose.


Why the heck should you want to "argue" useless abstracts instead of a practical, realistic scenario? As noted, the “abstract” was merely a handy example. I was not trying to indicate advocating one process over another.


Get your mind right and try again with something that's actually plausible. Nice Ad Hominem. I thought such derogatory personal remarks were not allowed here.


You aren't saying anything remotely signifigant to your topic of choice. Say something plausible about it and I'll listen. Until then you're just wasting space.My example was both significant and relevant. It is you who are trying to make it into something it was never intended to be.


Oh, now, after two and a half pages, you want to go back to the OP? That wasn’t me, that was you when you made this comment:
All these concerns have been addressed on this thread. The thread you're on now isn't about the technical feasibility of a space hab, but the psychological/biological aspects.I responded to your apparent concern about staying on topic. You ignored my relevant response.


You are the one who keeps coming back to this thread with assertions about the "superiority" of Lunar mining. Not at all. Each and every time, I am responding to either questions posed to me, or criticisms made regarding my comments.


Then you gave us an irrelevant fantasy about 1000 ton steel mills using exclusively Earth-adapted technology. Once again, as pointed out over and over, the actual size and technology was NOT the point of my comparison. It is you, not I, who keep trying to make that an issue.


You ignore any suggestion to research practical solutions. Hello. One last time. I was responding to your request that I explain why putting massive equipment on the Moon had advantages over putting it on a rotating space station. I pointed that out, using an arbitrary (http://www.onelook.com/?w=arbitrary&ls=a) example (http://www.onelook.com/?w=example&ls=a) to compare the effects of large amounts of necessarily moving mass.


Now, suddenly, you're complaining that I'm off-topic.
False. I never said, insinuated, indicated or otherwise alluded to any such thing.

MentalAvenger
2007-Nov-23, 12:10 AM
http://imagecache2.allposters.com/images/pic/RIC/2400-3868~Horse-Posters.jpg

The horse wasn’t dead, it just needed a little grooming. :)

Noclevername
2007-Nov-28, 08:37 PM
The rest of your junk can be ignored, but false accusations are over the line. :naughty:
Nice Ad Hominem. I thought such derogatory personal remarks were not allowed here.

Exactly what do you find "derogatory" or "ad hom" about it? Or is a disagreement now defined as an attack?

MentalAvenger
2007-Nov-29, 07:26 AM
An Ad Hominem, by definition, is a personal remark against the person, as opposed to a comment on the subject. Insinuating that there is something wrong with my mind is an Ad Hominem, and it was certainly derogatory. I was under the impression that those were not allowed here.

Noclevername
2007-Nov-29, 05:55 PM
Insinuating that there is something wrong with my mind is an Ad Hominem, and it was certainly derogatory.

I insinuated nothing, I used a common (I thought) figure of speech.

If it truly upsets you that much, I'll go change it. Apologies for the confusion, I meant no offense.

MentalAvenger
2007-Nov-29, 07:37 PM
It didn’t upset me. I was merely responding to your insinuation of false accusations.

Noclevername
2007-Nov-29, 08:31 PM
It didn’t upset me. I was merely responding to your insinuation of false accusations.

That was a statement, not an insinuation, and since you explained the problem I retract it. If you had never heard that saying, I can understand why you thought it an insult.

Van Rijn
2007-Nov-29, 09:46 PM
That was a statement, not an insinuation, and since you explained the problem I retract it. If you had never heard that saying, I can understand why you thought it an insult.

It was pretty clear to me - MA kept talking about putting a big steel mill designed for Earth on a space station, no matter how many times we pointed out that we were talking about designing purpose built hardware to work in the environment for which it is intended. It's clear he either didn't understand or was ignoring what we were talking about.

MentalAvenger
2007-Nov-30, 12:39 AM
It was pretty clear to me - MA kept talking about putting a big steel mill designed for Earth on a space station, no matter how many times we pointed out that we were talking about designing purpose built hardware to work in the environment for which it is intended. It's clear he either didn't understand or was ignoring what we were talking about.That is total ** on several levels. First, the “insinuation” reference here was that there was “something wrong with my mind”. THAT was a direct Ad Hominem, an insult, and clearly against the rules of the forum. So as far as it being “clear” to you, you weren’t even responding to the same comment that Noclevername was. (the one you quoted).

Secondly, as I explained repeatedly, and what you actively chose to ignore repeatedly, is that it wasn’t about the technology, or the size. It was a comparative example (http://www.onelook.com/?w=example&ls=a). Perhaps the concept of an arbitrary example used to illustrate a totally separate point is a little advanced for some people. I made it clear, over and over, that the point I was making was about the difficulty of having a manufacturing process, that necessarily moved large (and often molten) masses around, would be difficult and probably dangerous aboard a rotating “centrifuge” station. And that was the only point. It appears that my numerous detailed explanations fell on deaf (or closed) ears. Whatever.

Noclevername
2007-Nov-30, 01:00 AM
Perhaps the concept of an arbitrary example used to illustrate a totally separate point is a little advanced for some people. I made it clear, over and over, that the point I was making was about the difficulty of having a manufacturing process, that necessarily moved large (and often molten) masses around, would be difficult and probably dangerous aboard a rotating “centrifuge” station. And that was the only point. It appears that my numerous detailed explanations fell on deaf (or closed) ears. Whatever.

Well, perhaps the comcept of researching methods that would actually be practical in space is "a little advanced for some people"*. As in, methods specifically adapted to the environment. Such as those that would be needed, for instance, to adapt Earth methods of metal production to the environment of the Moon, which you seem to assume will be a walk in the park. We have zero experience with how molten metals act under .16g, so assuming it's easier there-- and that the difference in effort is enough to overcome the disadvantage of the gravity well-- is unwarranted.


* You complain about ad homs insulting your intelligence, and then come out with this gem. Bad show.

MentalAvenger
2007-Nov-30, 01:19 AM
Amazing, simply amazing. It truly boggles the mind. After all this, you still don’t get it. I don’t care which method you use for processing ore into finished steel or aluminum. That isn’t my point and never was. Use whatever process you want. The bottom line remains the same. If you are producing large amounts of metal on a rotating station, it will have all those problems I listed. Using the same process, or even a different process, on the Moon won’t have any of those problems. It isn’t an issue of process, but rather of mass. It involves moving ore, moving molten metal, moving finished metal products. Processing sufficient quantities to supply the needs I mentioned, making the process practical, would present problems in a rotating station that would not be an issue on the Moon.

And, BTW, electrical rail launch pretty much nullifies any problems with working out of the Moons rather shallow gravity well.

Oh, and thank you for the retraction. That shows you have class.

Van Rijn
2007-Nov-30, 01:21 AM
Amazing, simply amazing. It truly boggles the mind. After all this, you still don’t get it. I don’t care which method you use for processing ore into finished steel or aluminum. That isn’t my point and never was. Use whatever process you want. The bottom line remains the same. If you are producing large amounts of metal on a rotating station, it will have all those problems I listed.


Why is it on a rotating station?

MentalAvenger
2007-Nov-30, 01:26 AM
Apparently you have not followed the discussion you have been commenting on. IIRC, it was Noclevername who said that Asteroid mining ore processing would be done on a separate rotating centrifuge section of a space station. I was responding to that assertion.