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kppraki
2003-Aug-19, 11:02 PM
Hi,

How about brain storming and post NEW ideas to propel the New Generation of Space Crafts. Who knows, one of us could come up with a wacky idea, which has eluded us for decades. :)

rocketa
2003-Aug-20, 12:04 AM
Might as well start with maximum whacky...

For "instantaneous relocation"- It will take two similar objects one in each location the transmitting and the receiving. The Probability of each object's existence in its original location is minimized while the probablility of being in the second location is maximized. Since the masses are identical I surmise that no energy is needed; what is needed is this probablility generator?????

:blink:

Fraser
2003-Aug-20, 03:09 AM
We need an Improbability Drive from Hitchhiker's Guide to the Galaxy.

Planetwatcher
2003-Aug-20, 06:52 PM
I still would like to see something happen with nuclear energy.

At current technology we have little more ability then to make modified boiling water reactors, but hey, if we use that with hydrogen fuel, we can still travel 7 times faster, and 10 times farther then conventenional rockets, (in theory) which is far better then we have now.

Lacking that, further development of solar and or tachyon sails is our next best chance at getting out and about, at least in the solar system.

kppraki
2003-Aug-20, 07:38 PM
Hi :rolleyes:,

I have always wondered, as to why we can't piggy back our space craft, unmanned ofcourse, on a comet.

Comets travel over vast distances with great speed and may pass through some very interesting places, how about attaching the probes to the comet itself, and set the prob to gather as much info it can and beam it back or store the info if it can't.

we could even get the prob back to analyze it, if and when the comet returns to the solar system.

Basically trying to use a comet as a natural propulsion engine B)
Riding the comet seems to be a great idea for me.

Thanks
Praki

sky-high
2003-Aug-21, 04:06 PM
Rocketa, be nice, you're the expert, don't hit us metaphysically bro !


All the more since the question is serious. Talking about what can be done, sure, you could ride a comet if you want, kind of boring though, like a big dumb merry go round, due back in 75 years if you ride Halley or in a couple of thousand if it's the next one; before your second coming you are running the very serious risk of being caught up by real space vehicles developped before you were crossing Neptune's orbit.

Nah...We need real propulsion, meaning speed, meaning 100-200 km/sec. Now the idea of using atomic energy sounds nice; still there are two many risks, I mean look at the mess down here, we are unable first to tap all the energy in a radioactive material, to speed up the proceedings and to get the darned inert lead from uranium in two days not in 25,000 years. Just imagine what a space-leak would mean, to have the menace on an unstable orbit, spiraling down to us, implacably. Spooky...

That doesn't mean we have to reject it completely, for instance a nice long-tested nuclear reactor of the type that powers military subs, coupled with a nice ionic engine, already implemented by ESA on their SMART-1, now that would really open the Solar System.

Well, trouble with SF is that is very easy to miss the border with reality. Can you believe that I met 15 years old kids who were absolutely convinced that hyperdrive and teleportation were in use for years ? Adults are not much better sometimes, there was that splendid story about the radio-station used by Columbus to keep contact with his ships, sold in 1982 at an auction in NY. For a couple of millions, mind you ! And I bet that more than half of those present were sufficiently aware, scientifically and kept silent. I'd have done the same, I mean everybody is entitled to have a little fun, right?

But ( and now I'm speaking for real propulsion experts, like Rocketa ) wasn't there that simple electric engine effect, meaning that an electrically charged wire placed in an electromagnetic field will move perpendicular to that field ? Now to make a whole space-ship the equivalent of an elecric conductor, should not be that difficult. Remember the electro-hydro-dynamic propulsion in the '80-es? And you can't find a better and bigger magnetosphere than the Sun's, for light years around. So, did anyone ever tried to make a space ship move in the Sun's (or for that matter Earth's) magnetic field, like a part of the rotor (the moving part) of an electric engine ? CLASS, THIS IS DEAD SERIOUS ! I'm not fantasizing here. As the matrimonial adds are saying : serious replies only !

Thank you

Sky-High

pHoSfEe
2003-Aug-22, 06:24 PM
Hi everyone.

This isn't exactly an answer but more like an idea or suggestion to anyone who reads this.

I bet a lot of people have heard, read, or seen something about molecule-sized transistors. How did they do it? The technology was a hybrid of chemistry and electronincs. A transistor that small would enable us to make a supercomputer the size of our thumb. Now imagine a fusion of two different sciences like chemistry and electrnics (explained above) that could create a revolutionary invention. I have no idea what different branches of physics could merge together, but I hope you all get the idea.

- YMP

p.s. And um Sky-high? I'll have to leave that (the part about using the magnetic field to power an engine) to the experts scince I have ZERO experience in that field.

philip slater
2003-Aug-22, 11:42 PM
I saw the word serious. I can do serious. Doing serious without being heavy man now that is something.

This is serious. Anyone floating up a serious suggestion in a free and easy public-domain stormed-brain session takes on a heavy responsibility. If it is decided that you have a great idea the next thing will be to give it to a government to play around with or get a company to use shareholder's funds entrusted to it to build you an x million dollar or quid proof of concept prototype.

They might even do that, so long as you give them exclusive rights to the product so they can try to get back the money their investors trusted them with and show a profit in return for the risk. Like it might not actually work, or something even better might come along.

You won't be able to file for a patent if you have already disclosed the invention into the public domain, like here.

So if the idea looks good - and it’s your very own - just file it first with your national patent office, if you haven't done so already. Its usually not expensive for the first stage in most countries, which gives you time to sort out if it’s worth taking further. And it isn't really difficult, just a matter of learning and keeping the rules of the game.

Well worth the trouble - if you're serious.

Philip

sky-high
2003-Sep-04, 07:34 PM
I think gravity research is one possible answer. A gravitational propulsion system might not even be an engine, all you need would be a gravitational screen. Reduce or cancel the gravity in one direction and you'll get all the mass of the Universe pulling you on the other side. In fact on a resultant vector of the non-blanketed directions combined. The accelerations obtained would be practically limited only ty the speed of light...if even by that. You go straight into relativistics, head first.

See how simple it was :rolleyes: ? Now all you need to solve is the trifle of finding some field or material or influence trough which gravity does not pass. I got wind of experiments 60 years old with extremely powerful electromagnetic fields. Mediatized and romantcized under the generic title of "Philadelphia experiment". I wonder if they wouln'd influence local gravity or produce gravitational-like forces. Sure, you would need a few million Gauss field for that.

This is a serious questions for experts: far as I know the only item that can produce gravity is mass, in suitable amount. If there is another way, I would be extremely interested to find out.

sky-high

Planetwatcher
2003-Sep-05, 12:26 AM
In the Aug. this year Discover Magazine was another article about building faster space vehicles. It named 5 different means of propulsion aclaimed to do anywhere from 12% to 66% of light speed.

Fission, and fusion were each rated at 12%, Sails, and fusion ramjet at one quarter, to one half; and anti-matter as much as two thirds of light speed.

It cited sails and fission as the closest to reality, anti-matter as the most practical,
and fussion and ramjet as the most difficult or unrealistic.

The article said these advances are closer then we may think. Well, I'm still waiting... : :blink: Still waiting... :unsure: Still waiting... :ph34r: Still waiting.. :(

Arramon
2003-Sep-12, 08:30 PM
Magnetics is an interesting idea....

What if there were a huge magnetic plate at one launch center that repulsed a ship that was the exact opposite of the ground magnet..... would this squish the people inside? Would the magnetic repulsion even work with the gravitaional field of the earth being as it is?

In another post, someone mentioned as a side note that even magnets were stronger than gravity, because you could lift a metal object with a magnet, defying the gravity of earth.... the size of the object may matter, and so too the size of the magnet...

this may mess with other metal objects that come in range of it, unless the fields can be set to a certain.... what.... frequency? whatever magnetics use.....

Or even an attractor high up that would pull the object to it, instead of pull....
(how do they make zero G rooms that the astronauts train in?)

Why must consumable propulsion be used? There are plenty of other sources that attract, repulse, deflect, or alter things in their cousre..... like light, sound waves, gravity, wind resistance...

?? <_< hmmm..... nuclear power.... thats a nasty bit of technology just waiting to explode....

what if a ship were to circle the lower atmosphere enough times to gain enough momentum to escape the pull of the earth&#39;s gravity? or is that an opposite effect of what happens.... our ships seem to need to go straight up... what if we used gravity and let it swing our ships up... like a sling shot.... or maybe too much fuel would be used for that...


we need anti-grav elements NOW&#33;&#33;&#33;

They did it in the movie The Blackhole.... why can&#39;t we? =P

is there a certain alloy that can be used for this concept? one that is magnetically opposite of that of the earth&#39;s gravity? then again, if there were, they would be floating around everywhere right? hmm.... i&#39;m confusing myself...

its just getting beyond the pull of earth that is hurting our advancements in this field.... maybe the space elevator isn&#39;t a bad idea... transport the ships up, then use the propulsions in space.... save fuel for when its needed most....

..... :) ok i&#39;m done

. ..-={A}=-.. .

jrv
2003-Sep-12, 11:44 PM
Perhaps the use of Solar sails? It would be easier and probably a lot cheaper, for unmanned probes anyway.

apolide
2003-Sep-16, 01:02 AM
In my opinion it all depends on the timeframe.
If we want to get serious about exploration/colonization we need to find a viable approach to fast interplanetary travel using non-exotic propulsions, meaning systems based on widely accepted theories, reasonably cost-effective and using technologies and materials more or less available off-the-shelf.
In order to overcome the limitations of our current technology we surely need to think about the next phase of space exploration (ultra-fast interplanetary/slow interstellar), make a strategic choice between the conflicting approaches to the problem and finance adequately the research in the chosen area.
To move from slow to fast interplanetary travel without giving the usual trite answer "from 20 to 30 years" (meaning NEVER, unless we stumble upon some new discovery or we enter a Golden Age of space enthusiasm and economic bonanza) the only viable way, IMHO, is the combination of third-generation fission reactors with ion engines. We could achieve some good results improving the time-tested and reliable radio-isotopes fuel cells but to make a definite step towards real space travel we need to overcome the "probe ideology" and build real spaceships (i.e. capable of regular flights across the Inner System with an operational life similar to nuclear military ships -20/30 years). To achieve this, the only practical solution is a custom-built intrinsic-safety fission reactor to be mounted in a propulsion module as far away as possible from the living quarters. This to reduce the risks of radiological contamination and provide an escape when facing catastrophic breakdowns (statistically irrelevant but possible nevertheless).
The transition from fast to ultra-fast and slow interstellar will be the most difficult and will require either some theoretical breakthroughs (i.e. the discovery of the relation between gravity and electro-magnetism or an explanation of the concept of dark energy or an improved understanding of the characteristics of space) or a technological revolution (i.e. the creation of a viable infrastructure to produce relevant quantities of anti-hydrogen atoms, a cheap and possibly light container plus a more efficient method to convert the energy derived from matter-antimatter annihilation to electric power). In this case, considered the progress made both at the FermiLab and CERN laboratories, I would favour strongly research in the antimatter field. Anyway, it&#39;s just a question of money and political/popular will. When they say "in 50 years&#39; time" or crap like that, everybody knows it&#39;s just baloney. They forget to say "given current budget limitations". Nobody knows when we&#39;ll have a commercial fusion reactor or an anti-hydrogen production cycle capable of producing several grams per week/month. If they slash funding, both efforts will drown like the NERVA experiments in the early 70s. If they provide unlimited funds (completely irrealistic, I know) we could have them both in 10 years. It&#39;s all about the money, unfortunately. And until we space enthusiasts have something more tangible than dreams to show (i.e. a new Earth at 15-30 light years) everything will crawl forward like today.

PeterG
2003-Sep-26, 03:47 PM
The thing about spaceflight is that it takes an enormous amount of energy. Chemical rockets are to spaceflight what man-powered airplanes are to flying. Like the saying about a dog walking on its hind legs, its amazing that it can be done, not that it is done well. The difference between Charles Lindberg and Neil Armstrong is that Lindberg proved that with a little more development, anyone could fly across the Atlantic. Armstrong proved that it was a one-off billion dollar stunt. Which is a shame.

That leaves some as yet undiscovered technology to do it. It would be something that could produce orders of magnitude more energy than can be gotten from chemical reactions. If it could be found, it would also solve mankinds energy problems on earth as well.

Of all of the who-knows-if-it-will-work wild ideas out there, the one that appeals to me is the concept of nano-fusion. There is a tiny bit of it to be found on the web. Fusion does seem to be the necessary energy source. Fusion of Hydrogen and Boron produces only alpha particles, which are high energy electrons which could be converted directly into an electric current (without having to boil water as an intermediate step).

The nano-fusion model is intrigingly the exact opposite of the Tokomak model. That "bomb in a box" model is to get a bunch of gas and get is so hot and so compressed that the there is a high probability that the atoms hit each other with enough force to get a lot of fusion to happen. You take a huge machine and create one small where by shear blind brute force you force the probabilities to be right.

The nano-fusion model is more like biology than physics. Instead of one huge machine, you have millions of tiny devices that each work (like biology) at the level of direct atomic / molecular manipulation. (My wife works in a lab where they study the chlorine ion channel in cell walls. Cells do non-stochastically manipulate atoms.) The idea is you etch tiny atomic level linear accelerators and guide individual atoms into each other. The reaction would depend on steering the atoms, and not on a probabilistic threshold of them hitting. Maxwell&#39;s demon does not work with heat, because the energy needed to detect and seperate the atoms is more than the energy of the heat you are seperating. However, it might work if the energy you get out of it is much more than the detection energy needed.

A large scale nano-fusion reaction would look more like a large muscle, rather than a large bomb in a large box. Like a muscle, it would be made up of millions of cells, each performing individual atomic scale actions.

Given that there is already a billion dollar silicon chip fabrication industry that is learning how to make atomic scale electrical components, and given that the "bomb in a box" technology has been "20 years away" for about 30 years now, and given that Maxwell&#39;s demon arguably could work for nuclear reactions, it sounds like something worth persuing. I may turn out to be impossible, but it at this point, to me, sounds like the most plausible. Unlike entirely exotic things like warp drives and what not, it is something that could be checked out now. Most of the checking out would simply involve anaytical design.

Matthew
2003-Oct-10, 11:22 AM
Anti matter engine would be great. But my personal favourite would be a pure energy engine. How it would work I don&#39;t know, but I think it&#39;d be great, but thats all I have toying in my head a &#39;pure energy engine&#39;. I don&#39;t know how it could work but yeah thats my wacko (but possible, i don&#39;t know how though) idea.

Haglund
2003-Oct-10, 12:47 PM
To create antimatter takes quite a lot of energy, but there lies its advantage as a fuel, because in contact with matter, the result is energy. As I understand it, there will be complete annihilation. There is a problem how to store the antimatter, but scientists are working on this as well, by simply containing it with a magnetic field inside the tank. It would require very little for a journey to Mars, perhaps a few gram only. On really long journeys into space, this might be a good solution when speed is important. But, I see antimatter being used in future spacecrafts. The question is when...

I can&#39;t really think of any propulsion that hasn&#39;t already been thought up by someone else, but one idea that would be great if it worked, would be if we could shield the spacecraft from the Earth&#39;s gravity field before lifting it up.

Matthew
2003-Oct-11, 05:23 AM
How about a spaceship launched from Earth using a superfluid track. Superfluids are a substance which has no friction. So a space ship could run over this superfluid track and acieve speed very quickly and all it would have to contend with is friction from the air. Maybe run the track downhill and just before the end of the track turn the track up a hill, activate boosters, effectivly launching it into space. All we need to do is create an effective superfluid...

imported_Draco
2003-Oct-11, 11:45 AM
I have an idea...
Not sure if people will understand:

There could be this satellite, and it is connected to 2 other smaller satellites. Once in orbit, it could start to spin around, the middle satellite, which controls the outer 2 starts to spin, therefore the outer satellites start to go along with it. Just say it could spin 360degrees, right, ok then maybe it could still be spinning for a few months, accelerating, until it has reached a very high speed. The outer satellites could then be flunged out, propelled. They &#39;should&#39; go speeding away from the earth, and as they accelerate, the ion engine could fire up and away they go&#33;
Not sure if this can make satellites faster, but just an idea:)

Arramon
2003-Oct-14, 03:06 PM
how would you stop the spinning in order for the ion engine to work?
if you were still spinning, the engine would go berserk and probably shoot the satellite off into any possible direction or just fling it around until it was turned off...

The superfluid thing might work, and the air restriction could be lessened with the new plane tip they have now, helping prototypes go up to 5000 mph.... mmmhmmm thats fast...

like a giant slip and slide&#33;&#33; =)

but, what happens to all the KY jelly...? :o

imported_Draco
2003-Oct-18, 08:14 AM
Well wouldn&#39;t the satellite be flunged out then the ion engine could start? :)

kashi
2003-Oct-19, 02:32 AM
We&#39;re a long long way off creating a gram of anti-matter, not to meantion sheilding a ship from the Earth&#39;s gravitational field? New generation of spacecraft hey? This sounds more like the year 3000 not the year 2020.

imported_Draco
2003-Oct-19, 04:50 AM
Year 3000...such a long way away&#33; :&#092;

Haglund
2003-Oct-19, 09:56 AM
It wont take a thousand years to reach the technology it takes to build antimatter propulsion, the first experimental spacecrafts could be built within a few decades perhaps.

Planetwatcher
2003-Oct-20, 01:51 AM
It wont take a thousand years to reach the technology it takes to build antimatter propulsion, the first experimental spacecrafts could be built within a few decades perhaps.
I would tend to aggree with Parker.
But it&#39;s still not too likely that even anti-matter will get up near the speed of light in this century.

Dave Mitsky
2003-Oct-20, 06:59 AM
At the monthly ASH meeting last Monday an emeritus professor of physics from a local college gave a talk on nuclear propulsion. The outlook is surprisingly grim. Nuclear fission techniques are the most likely to be realised any time in the foreseeable future. Antimatter propulsion is only a pipedream, as he put it.

Dave Mitsky

Haglund
2003-Oct-20, 12:06 PM
Antimatter propulsion could be reality within a hundred years perhaps before that (and I&#39;m talking about small to moderate sized unmanned missions). It takes a lot of energy and time to produce the necessary antimatter though. Then there&#39;s many other things to develop of course.

I&#39;m not sure how much research is going on at the moment, but here are two links:

http://www.engr.psu.edu/antimatter/
http://www.engr.psu.edu/antimatter/introduction.html
http://science.nasa.gov/newhome/headlines/...op12apr99_1.htm (http://science.nasa.gov/newhome/headlines/prop12apr99_1.htm)

Dave Mitsky
2003-Oct-20, 12:36 PM
I&#39;m aware of some of the research. The fact that NASA is conducting some of it is not reassuring.

From the final link:

"Right now, antimatter is the most expensive substance on Earth, about &#036;62.5 trillion a gram (&#036;1.75 quadrillion an ounce). The production is, at best, 50 percent efficient because half of what&#39;s created are regular protons, and the equipment now used was not designed to fuel rockets. Harold Gerrish of NASA/Marshall and others estimate that improvements in equipment to slow and trap the antiprotons could bring the price down to about &#036;5,000 per microgram."

&#036;5,000 per microgram equals &#036;5,000,000 a gram&#33;

The problem of containment is a considerable one. Ideally one would want to produce anti-deuterium and liquify it but magnetic fields won&#39;t work then as a containment method.

I&#39;ve read an article somewhere that claimed that at the current rate of anti-proton production it would take the electrical ouptut of the entire planet for 300 years to produce enough anti-matter for a trip to Alpha Centauri.

Dave Mitsky

Arramon
2003-Oct-20, 02:31 PM
Originally posted by Dave Mitsky@Oct 20 2003, 12:36 PM
"Right now, antimatter is the most expensive substance on Earth, about &#036;62.5 trillion a gram (&#036;1.75 quadrillion an ounce)..." &#036;5,000 per microgram equals &#036;5,000,000 a gram&#33;
=) I like that decrease in cost...
Talk about exponentially smaller. At that rate it&#39;ll be free in a few years&#33; :unsure:

Gotta get what we need before we get what we want. Forget alpha centauri...
We&#39;ve got plenty of ground to cover over here. Plus, we&#39;ve got a fat sun on our door step with plenty of energy to consume... Throw some solar panel collectors/conduits/transistors right close to it, let it absorb/reflect/deflect/transfer/power/channel whatever energy it can and give us our light speed&#33;

:blink: oi&#33;

. ..-={A}=-.. .

astrophysicsrose
2003-Oct-22, 08:36 PM
Propulsion is one wonderful adventure, newer ways, but, the time element inherent within and comprising a human life is something no one has considered. How will this physical form, if traveling faster than light speed, ever maintain it&#39;s essential time element? Death will occur, it&#39;s inevitable. Instead of wasting time trying to consider propulsion, which, if done at faster than light speed resulting in the dissipation of the human essence at the control panel, why not consider the creation of a stargate.

Idea seems just as dangerous to the time element inherent within human life, but, it may be more feasible than traveling at faster than light speeds. Humans are comprised of three essentials. Those being the divine spark, the flesh, and TIME. And friends, if a ship is to travel faster than light speeds in order to reach a destination in a plaubible amount of reality time, then, those high speeds will just cause the human form to loose it&#39;s essential birthrite, that being time, the time element will dissipate, and death will occur. Perhaps the stargate concept holds some scientific credibility for those who desire interstellar communion.

Matthew
2003-Oct-23, 06:39 AM
As technology increses and as we begin to understand antimatter more (and how to make it), we may be able to make it cheaper, but it&#39;d take a massive leap in physics and technology. But massive leaps have occured before, all it takes is for someone to suddenly have a great idea. How often great ideas come around...

Haglund
2003-Oct-23, 07:31 AM
I know that it is incredibly expensive to create antimatter, but it doesn&#39;t have to be like that forever. However I do think it&#39;s possible to start experiments with it within decades, I don&#39;t think it will become our primary fuel for quite some time.

Matthew
2003-Oct-23, 08:12 AM
Parker, we&#39;re already making antimatter, extremely small amounts but we are making it. We need to be able to &#39;streamline&#39; the process.

trevor
2003-Oct-24, 06:51 PM
Astronaut Franklin Chang-Diaz has been working on developing plasma rockets. If they were developed for a mars mission, the engines would be able to be firing during the entire journey.

Haglund
2003-Oct-26, 09:01 AM
Originally posted by matthew@Oct 23 2003, 08:12 AM
Parker, we&#39;re already making antimatter, extremely small amounts but we are making it. We need to be able to &#39;streamline&#39; the process.
Yes and what is needed among other things is cheap energy, such as if we had a giant surplus of energy it would bring the cost down, but it is also a slow process. I am sure we can make it faster and cheaper in the future. If we can, then that will be an important door opening to fast interplanetary travel.

Hunter
2003-Oct-28, 06:48 PM
Ah, space propulsion. My favorite topic&#33;

The next generation of spacecraft is going to be nunclear-powered, no ifs, ands, or buts. Regardless of whether you like it or not, nuclear power is safer than your car, if it&#39;s handled well. If you&#39;re worried about radiation, well, that&#39;s like being worried you&#39;re going to get wet by spilling your glass of water on yourself, while floating in an intertube in the ocean. There&#39;s a lot of radiation in space already.

With nuclear power, we can go electric (like an ion drive) or thermal. Currently, ion drives, even with nuclear power, are much too slow and weak for human spaceflight. The solution, is nuclear thermal. Basically, propellant (most likely hydrogen) gets passed by the reactor and is heated up, then pushed out the rear of the craft. The hot emitted gasses produce thrust. And no, there&#39;s no danger of it spewing radiation in the exhaust, if the engine is designed right. All that&#39;s transferred, is heat.

The US did research into this int he 60s, and it was called NERVA. It was cancelled because of public fear of anything nuclear. What is this? The dark ages? Anyway, NASA has started research into this again.

For the near term, though, my personal choice is plasma propulsion, aka VASIMR. Heat hydrogen into a plasma state with radio waves(similar to your microwave oven), then expel it out the back, containing the plasma with magnetic fields. With this scheme, you can accelerate continously to Mars, maintaing some artificial gravity(1/2 to 1/2 of Earth&#39;s), and avoiding problems with bone marrow loss and muscle atrophy due to lack of gravity.

And here&#39;s the good part: This technology has matured enough to start being flight tested now. The only thing missing, is a nuclear reactor capable of producing 12 megawatts(MW). We have the technology to build such a reactor, we just need to certify one for spaceflight. And it&#39;s a precursor to fusion engines. Remember this name: Dr. Franklin-Diaz. He&#39;s the brain behind it at NASA&#39;s JPL. He&#39;s even got a ship named and designed: the Bekuo (shooting star).

The other upcoming technology that shows promise is M2P2, also known as Plasma sails. Basically, create a magnetic "bubble", fill it with helium gas, and let the solar wind push the bubble along. Excellent protection against space radiation, but lack of artificial gravity is a problem.

Fusion and antimatter are out there, and will be awhile before we get them to work, and work cheaply. These are end of the century technologies. We may get them working before then, however.

kppraki
2003-Nov-10, 01:20 PM
One interesting link B)

http://www.eurobrasil.at/scientific_cage/a...keoff_0009.html (http://www.eurobrasil.at/scientific_cage/archive/takeoff_0009.html)

cheers
P

Planetwatcher
2003-Nov-10, 07:09 PM
The solution, is nuclear thermal. Basically, propellant (most likely hydrogen) gets passed by the reactor and is heated up, then pushed out the rear of the craft. The hot emitted gasses produce thrust.
What is being described here is a glorfied version of 1960s nuclear technology known as the boiling water reactor. The nuclear reaction superheated water into steam, which operated a turbine which generated the electricity.
It&#39;s been since dubbed as the most expensive means ever to boil water, and the described way to superheat hydrogen is no different.

That&#39;s not saying it&#39;s not a good idea, because it is a decent starting point to develop nuclear propulsion technology. However it is very limited when compaired to finding a means to achieve propulsion directly from the nuclear reaction.

Consider the explosive power of an H bomb. If that power could be better controled, and directed as space craft propulsion thrust, and made to last long enough for a good thrust burn, then you have true nuclear fission propulsion.
That kind of propulsion has been estimated to achieve between 12% and 20% of the speed of light.

Nuclear fussion when we learn how to use it is more promising as being 8 to 10 times more powerful then fission. It is estimated to propell space crafts up to 60% possibley as much as 80% of the speed of light.

That could take us to the helopause, (where Voyager 1 is now, and took over 30 years to get there) in just a few days.

Arramon
2003-Nov-12, 11:12 PM
You mean the heliosheath, yes? =)

I just hope we dont blow something up that we may need to survive...
namely the earth...
Nothing like crackin a tectonic plate or something to get the Earth bubbling and ready to start a whole new life cycle.

=P

Rajiv
2003-Nov-16, 03:53 PM
Hi

I think the simplest and cheapest technologies and one that is most possible in the near future will be the space elevator. Only if we see a dramatic lowering of costs involved in putting objects to space can we look forward to the "second space revolution". To gather more information on the space elevator project go to the following link.

http://www.isr.us/SEHome.asp

In my view the genesis of space flight will have to follow the following trajectory

a. Generation of pressures for interplanetary scale driven by either
1. demographic pressures on earth ( population explosion )
2. security considerations ( asteroid impact etc )
3. commercial interests ( cheap mining technologies on other planets, asteroids etc)

Such a situation will arrive only once cheap means of transit to space is available. Once that is there in a matter of a hundred years or so we will see the advent of commercial space colonies and the attendant technological breakthroughs. If commercial settlement of other planets occur and if there are other colonies( read scientific missions) that do research on harvesting other planets then we may see the advent of another space revolution. Can you guess what that can be and how long it would take to happen ?
And as a parting guesture of course our last space revolution of that started in the 1960s fizzled out in the end of the 80s. We are waiting for the next space revolution. Perhaps most of us will be alive to see it happen in the next 25 years.

Regards
Rajiv

Planetwatcher
2003-Nov-16, 09:25 PM
Okay, Arramon is correct. It is heliosheath. Now here I&#39;ve been calling it helopause everywhere else and the others seem to understand (I think) what I&#39;m refering to.

I believe Rajiv is also correct and to my dismay agree with him quite totally.

imported_Ziggy
2003-Nov-18, 12:11 AM
We all have lots of theories. Here&#39;s the most commen ones fusion,fission, solar sail,matter-antimatter,plasma,ion,warping, and of course the wormhloe. Each one has it&#39;s advantagaes and disadvantages. And each one is not getting the right funding. GOD DAM IT DON&#39;T THOSE PEOPLE SITTING IN THE WHITE HOUSE KNOW HOW IMPORTANT THIS IS&#33;? Next time I post here hopefully I&#39;ll have a theory thats fesible and technologicly sound.




"The Earth is like the cradle of life, but one cannot live in the cradle forever"

hubble
2003-Nov-18, 05:24 AM
Originally posted by Ziggy@Nov 18 2003, 12:11 AM
We all have lots of theories. Here&#39;s the most commen ones fusion,fission, solar sail,matter-antimatter,plasma,ion,warping, and of course the wormhloe. Each one has it&#39;s advantagaes and disadvantages. And each one is not getting the right funding. GOD DAM IT DON&#39;T THOSE PEOPLE SITTING IN THE WHITE HOUSE KNOW HOW IMPORTANT THIS IS&#33;? Next time I post here hopefully I&#39;ll have a theory thats fesible and technologicly sound.




"The Earth is like the cradle of life, but one cannot live in the cradle forever"
most likely america or japan could complete this opperation(technology wise) and they will , i think use a nuclear launcher :blink: :P :unsure: ;)

Scully
2003-Nov-18, 06:02 AM
Nuclear is so 20th century

lol

Rajiv
2003-Nov-19, 03:05 AM
Hi

I feel that frequent manned interplanetary flight is just round the corner about a hundred and fifty years or so. But what will drive people to go to other planets - tourism, science ? No I dont think so. Of course manned missions would start in about 25-50 years and will increase in frequency with time. But given the odds can we really think of people settling down on the moon or mars ? That will be a major bottleneck which humanity will have to overcome ? We have technologies now under developement (and expected to be mastered in about 10-15 years) that will cut down the time of travel to ( say ) mars down to 3 months. By the way I feel that once humans start colonizing the near planets it will be a watershed in human history. It will change not only our overview of life but other things like genetic changes etc may become a necessity of colonizing other planets.
See the point i wish to make is that the problem probably is not the technology involved. We may perfect it in some years time. The problem really is the motivation needed to drive mass migrations and developement of very large scale commercial interests on other planets to encourage people to go there. That I think is really a very long way off.
Coming back to the point of my earlier posting I believe that it may take a thousand years or more before humankind really has the technology or the will to venture out of the solar system.
The third space revolution will probably involve interstellar travel. This may initially start as unmanned scientific expeditions and then manned ones ( though I feel that will again be a very long way off ) . The huge amounts of energy required to get to ther nearest stars in a reasonably small amount of time would require
a) A larger human lifespan ( probably 5 times more, twice I think is achievable within the next couple of hundred years )
B) A vast energy source ( maybe once humans learn to harvest jupiter for hydrogen , perfect controlled fusion and other technologies like very large scale plasma or ion propulsion )
c) Colonization of at least some of the satelites of the outer planets ( in order to have the support infrastructure to build and launch such spacecrafts)
d) A host of other technolgies will be needed to understand the dynamics and hazards of extremely high speed space flights.
Again all said and done the motivation for humans to leave the solar system for the stars has to be something really extraordinary. Well I cant think of any for the moment ? can you ? As for those who say that humans will go to the stars for the reason that it is there, all I will say is this - there is an equally forbidding frontier has never been colonized - the oceans - even though it is there and has always been.
Well if we do manage to reach the stars and scatter our seeds in the milky way we may see many other revolutionary ideas of space travel coming up which may be very difficult to comprehend at this point of time.
Would Welcome your opinions all these issues.

Regards
Rajiv

joetommasi
2003-Dec-09, 07:50 PM
I don&#39;t know what it means but last year I made something that used static electricity and if an object was placed inside it, the object lost a little bit of weight. I wonder if that idea can be used to make things light enough to fly?

Arramon
2003-Dec-09, 09:23 PM
Human technology may be out of the solar system before we even realize it... Voyager 1 & 2... still alive and kicking... =)
If the sensors keep working, we&#39;ll have information about the actual makeup of the Interstellar Medium.
The static electricity idea is interesting. Wasn&#39;t that what was used for the static bumpers on the vehicles in the Matrix movies?
With international interest in space becoming stronger and stronger nowadays, and in such a short time, from the 50s til now, I think the human race may find ourselves putting around this solar system sooner than 200 years. Mainly only for the big buck corporates at first, unless more forms are written concerning the exploration and advancements in space, but the private sector should come in just after, maybe even just before, to help fund the developement of the technologies needed.

. ..-={Arramon}=-.. .

Biscay
2003-Dec-13, 01:54 AM
Wormholes are my bet. Creating some kind of stargate, bending space and time. Im not sure if I understood what I red last day but travelling through one of these, means moving not only in space but in time too. We only need to find one of these particles, which are found almost everywhere, irradiate it with some kind of wave, similar to the one generated by the Big Bang, send the spacescraft, and close the hole with laser. No fuel, no problem.
What about lightspeed? As the spacecraft reaches this speed, time within the craft slows down. This means that if an astronaut travels in space at ligtspeed for what he thinks is two years, will find when arriving back home, that his new-born child died at 90 years of age 20 years before his arrival.

Matthew
2003-Dec-13, 05:41 AM
What about lightspeed? As the spacecraft reaches this speed, time within the craft slows down. This means that if an astronaut travels in space at ligtspeed for what he thinks is two years, will find when arriving back home, that his new-born child died at 90 years of age 20 years before his arrival.

It&#39;d work, accelerate your astronauts to as close to c as possible and then they can go to a lot of places in the universe, for they&#39;ll still be alive. A 100000 ly journey may only seem to take no time at all. But for people at home waiting for their return would need to wait 100000 years. Thats if they could be accellerated to c.

kashi
2003-Dec-15, 04:09 AM
But if you could be accelerated to c, infinite time would pass to people outside the spaceship before the astronaut physically "pressed the button" to make the ship slow down. This couldn&#39;t be overcome even if the slow down was automated, as time would stop.

Matthew
2003-Dec-15, 05:16 AM
But Kashi that brings up a paradox. You&#39;d be everywhere in the universe at the same time for all time. If you could not slow down from c, you would be travelling at c for ever but also in an instant. From someone on the outside of the craft you would be travelling at c for ever, though to you you would have travelled for only an instant. So you would continue to travel at c until the Universe came to its end, if it will have one, in an instant. But if the universe will never have an end you will travel forever, in an instant.

GOURDHEAD
2003-Dec-15, 03:46 PM
Let&#39;s dance with, at least confront, the devil in the details of propulsion required for interstellar travel. I choose to set aside, for the moment, processes requiring wormholes, and the harnessing of vacuum energy. In the case of wormholes, I doubt that they exist and even if they do I doubt they can be safely navigated in a predictable way not to mention our collective lack of knowledge about them. In the case of vacuum energy, if it exists and is harnessable, our lack of knoledge is overwhelming.

Fusion and matter/anti-matter processes can provide sufficient energy, but only energy, not propellants, without which the energy does not move the ship (brownian motion doesn&#39;t do much other than rip the ship apart if carried to extremes). This leaves sail effects and ion propulsion as the most promising candidates, and each lends itself to development from a currently strong knowledge and technological base as presented in http://hometown.aol.com/malcolmbmcneill/In...ationExplo.html (http://hometown.aol.com/malcolmbmcneill/InterstellarTransportationExplo.html)

The mass of from 10^17 to 10^19 tons of propellant, in addition to sail force, are required by a 12,000,000,000 kilogram ship to reach the Alpha Centauri system, the nearest known system. Propellant mass is the big problem&#33;&#33; :o

Faulkner
2003-Dec-23, 05:40 AM
What we need is unlimited energy. From what I&#39;ve read, quantum physics has proven that the vacuum is thriving with unlimited energy. The problem now is a technological one: how to harness that energy. If it can be captured, channelled, etc, then something like Alcubierre&#39;s "warp drive" becomes reality&#33; Maybe faster-than-light travel is just round the corner???

Alternatively....

Apparently galaxies have their own magnetic fields. Maybe we can use some kind of magnetic propulsion that "repels" itself along these magnetic flux lines?? Of course, the engine would have to be "monopolar" (ie either "north" or "south" pole)...thus it could be magnetically repelled...perhaps...maybe...??

damienpaul
2003-Dec-23, 05:47 AM
Faulkner makes an interesting point - something aliken to a gravitational slingshot used by probes etc....(i hope i interpreted this right)...perhaps a combination and sythesis of everything that we know of....is that possible?

Faulkner
2003-Dec-27, 05:58 AM
Can an appropriate arrangement of gears & pulleys be assembled that provides thrust enough to propel a mass forward? I&#39;m thinking a kind of assymetrical gyroscope...maybe you could just wind it up & move&#33;?