PDA

View Full Version : What's the fastest a human made object has (or presently can) travel?



DyerWolf
2006-Aug-16, 06:48 PM
I am curious as to how fast we can get something to move. (aka a spacecraft - not something like "fricken lasers" [even those attached to sharks]). I am wondering how long it would take a fast spacecraft to travel to one of the outer planets, and the speed it would likely be travelling(presuming we launched at a time when the earth and outer planet were on the same side of the sun...).

Are our spacecraft moving at even a percentage of the speed of light?

Saluki
2006-Aug-16, 08:04 PM
It all depends on how big of an object you want to accelerate. In particle accelerators, we get subatomic particles up to significant fractions of the speed of light. As far as objects big enough to feel/touch, the fastest I am aware of were the Helios probes, which made extremely close passes to the sun, and reached speeds upwards of 150,000 mph (roughly 250,000 kph).

However, you question relates to missions to the outer Solar System, where the extreme Solar gravitational forces that accelerated the Helios probes are not available. The best example of a high-speed outbound probe is New Horizons, which is currently traveling at a velocity of about 54,000 mph (24 km/s) with respect to the Sun. Its speed will vary on its trip to the outer Solar system, but it will take roughly 10 years to reach Pluto.

With larger rockets and/or a more ideal planetary alignment for multiple gravitational assists, it would be theoretically possible to make that trip faster, but not by more than a couple of years.

Regardless, you will never see planetary probes or inter-planetary spacecraft within the Solar system travelling much faster than this simply because of the extreme amounts of energy required to slow back down when you reach your destination. If a probe passed Pluto at any significant fraction of the speed of light, you would have very little time to collect any data. As it is, at the speed of New Horizons, the project scientists are going to really have to hustle during the few months when New Horizons is close enough to the Pluto system to get good pictures/measurements.

Lord Jubjub
2006-Aug-16, 10:38 PM
However, probes that have been launched toward the sun have reached speeds above 500,000 kmph.

Van Rijn
2006-Aug-17, 03:13 AM
Here's a somewhat related topic:

http://www.bautforum.com/showthread.php?t=40282

Keep in mind that the "fastest man made object" has little relevance to the issue of getting spacecraft to a destination quickly. That depends on feasible propulsion technologies and economics.

Kaptain K
2006-Aug-17, 08:55 AM
...presuming we launched at a time when the earth and outer planet were on the same side of the sun...
Probes are not (usually) launched when the two planets are on the same side of the Sun. Or, at least, that is not the relevent factor. Probes are launched when the trip is most economical. For example, Mars probes are launched when Mars is on the opposite side of the Sun from Earth, because by the time a probe on the most economical orbit gets to the orbit of Mars, Mars will be at that point in its orbit.

DyerWolf
2006-Aug-17, 02:58 PM
Thanks for the link. Looks like the other post was virtually identical (guess great minds think alike (although I am only running a 'great mind' emulation program until I get my upgrades...))

So I guess that if it takes a probe 10 years to reach Pluto, and Pluto is about 39.5 AU away, and the nearest star is 272,061 AU; at our present technological level it would take 6887 years or so for us to get a probe to another star system to check out their planets up close. Guess I'll have to put off my plans for intergalactic conquest for a couple of millenia. Sigh.

Kaptain K. - thanks for reminding me about trajectory. You would think an old tanker would remember that you have to lead a moving target.

Anyway, I appreciate your thoughtful responses.

Saluki
2006-Aug-17, 05:38 PM
We could probably work out something a little faster if we are talking interstellar distances. Some sort of nuclear drive could get speeds significantly faster. Other possibilities are ion drives and solar sails. However, we are still talking time scales on the order of multiple centuries to the nearest stars. We need some incredible technological breakthroughs to bring an interstellar trip down to something a single generation of humans could see to the end.

Also, remember that the faster we get there, the harder it will be to slow down when we arrive.

DyerWolf
2006-Aug-17, 07:28 PM
http://www.bautforum.com/showthread.php?t=37223&page=4

in this link it says that Voyager is faster- travelling at 17 km/s where as NH will only be travelling at 13 km/s (due to fewer gas-giant gravity assists) when each reaches 100 AU.

I know the heliocentric speed quoted below (above?) is 24 km/s: is the discrepancy due to the craft's slowing down as it travels? Is there another explanation?

Saluki
2006-Aug-17, 08:10 PM
It is currently traveling at 24 kms. As it climbs out of the Sun's gravity well, it will slow down. It will get a boost when it is near Jupiter, but then start slowing again.

Van Rijn
2006-Aug-18, 04:57 AM
http://www.bautforum.com/showthread.php?t=37223&page=4

in this link it says that Voyager is faster- travelling at 17 km/s where as NH will only be travelling at 13 km/s (due to fewer gas-giant gravity assists) when each reaches 100 AU.

I know the heliocentric speed quoted below (above?) is 24 km/s: is the discrepancy due to the craft's slowing down as it travels? Is there another explanation?

Voyager is doing quite well for current technology. Given enough money, one way to do a bit better would be a powered gravity assist (http://en.wikipedia.org/wiki/Gravitational_slingshot#Powered_slingshots) around the sun. You would send a probe on an upper stage to make a close approach to the sun, then fire the booster at perihelion (closest approach). Of course, it would go past whatever target it is sent to more quickly.

neilzero
2006-Aug-20, 12:54 PM
500,000 kilometers per hour is 139 kilometers per second. Can any one confirm that as a peak speed during a near miss of the sun?
Even if we can average 100,000 miles per hour to Centrii, (24 trillion miles) = 240 million hours = 10 million days = 27,379 years travel time. Actually it is about 4% farther to the three stars in the Centarri system. How far away will they be in 28,000 years due to proper motion?
If we are going to Centarii, we should likely state our speed relative to Centarii, not relatve to the sun = 24 kilometers per second plus an amount added vectoraly. Neil

Bob
2006-Aug-21, 05:52 PM
The Helios I and Helios II space probes did indeed set the speed record, but the speed was "only" about 250,000 km/hr, about half what isw stated above.

http://en.wikipedia.org/wiki/Helios_probes

hillbilly
2007-Jul-30, 10:23 PM
I am curious as to how fast we can get something to move. (aka a spacecraft - not something like "fricken lasers" [even those attached to sharks]). I am wondering how long it would take a fast spacecraft to travel to one of the outer planets, and the speed it would likely be travelling(presuming we launched at a time when the earth and outer planet were on the same side of the sun...).

Are our spacecraft moving at even a percentage of the speed of light?

A: In fact the fastest space shuttle's built, fly (in space) at speeds of 150,000+ mph...light in-fact travells at around 6,000,000,000+ mph...in answer of your question, man made spacecraft travel at speeds far from that of light! :lol: x x x

hillbilly
2007-Jul-30, 10:25 PM
A: In fact the fastest space shuttle's built, fly (in space) at speeds of 150,000+ mph...light in-fact travells at around 6,000,000,000+ mph...in answer of your question, man made spacecraft travel at speeds far from that of light! x x x

Tucson_Tim
2007-Jul-30, 10:26 PM
A: In fact the fastest space shuttle's built, fly (in space) at speeds of 150,000+ mph...light in-fact travells at around 6,000,000,000+ mph...in answer of your question, man made spacecraft travel at speeds far from that of light! :lol: x x x

Since orbital speed is around 18,000 MPH (relative to the Earth), when did the shuttle do 150,000 MPH? And relative to what?

Van Rijn
2007-Jul-30, 10:32 PM
A: In fact the fastest space shuttle's built, fly (in space) at speeds of 150,000+ mph...light in-fact travells at around 6,000,000,000+ mph...in answer of your question, man made spacecraft travel at speeds far from that of light! :lol: x x x

Welcome to BAUT, hillbilly.

A couple of points. The speed of light in a vacuum is about 670,616,629 miles per hour. The space shuttle can move at roughly 18,000 mph in orbit around Earth.

hillbilly
2007-Jul-30, 10:39 PM
Since orbital speed is around 18,000 MPH (relative to the Earth), when did the shuttle do 150,000 MPH? And relative to what?

A: I have read before than on a shuttle launch they tested what the speeds an apollo rocket couild perform. I unfortunately have forgotten what excact apollo rocket was tested. It managed to reach speeds (not in orbit to earth) of 150,000+ mph!

EvilEye
2007-Jul-30, 10:58 PM
We have the technology and knowhow to build a near lightspeed ship.... but we will never have the money.

Van Rijn
2007-Jul-30, 11:22 PM
We have the technology and knowhow to build a near lightspeed ship.... but we will never have the money.

What technology are you referring to?

Van Rijn
2007-Jul-30, 11:28 PM
A: I have read before than on a shuttle launch they tested what the speeds an apollo rocket couild perform. I unfortunately have forgotten what excact apollo rocket was tested. It managed to reach speeds (not in orbit to earth) of 150,000+ mph!

There were the Helios probes (not Apollo):

http://en.wikipedia.org/wiki/Helios_probes

There were two in the series, Helios I and Helios II. They were launched to orbit and measure the Sun. They set a speed record for spacecraft at 252,792 km/h (70.2 km/s). They also set the record for closest approach to the Sun, at about 45 million kilometres, slightly inside the orbit of Mercury.

cjl
2007-Jul-30, 11:30 PM
A: I have read before than on a shuttle launch they tested what the speeds an apollo rocket couild perform. I unfortunately have forgotten what excact apollo rocket was tested. It managed to reach speeds (not in orbit to earth) of 150,000+ mph!

It's incorrect then.

The fastest Apollo rocket (not the shuttle) was the Saturn V, which took the capsules up to about 11km/s, or about 24,000mph.

Bearded One
2007-Jul-31, 01:00 AM
A related question is which spacecraft obtained the fastest speed not including gravity assist maneuvers. In other words, which spacecraft had and used the highest self-provided delta V. New Horizons perhaps?

Lord Jubjub
2007-Jul-31, 01:46 AM
Yes, New Horizons had the fastest launch speed of anything from Earth.

cjl
2007-Jul-31, 01:46 AM
That is a strong possibility for most total spacecraft provided delta v. What was the total delta v on Deep Space 1?

astromark
2007-Jul-31, 07:32 AM
Slow down a bit... I am not keeping up. You are throwing numbers at me that I do not understand. I am easily confused,:)
I understand 11km/s. as the velocity required to leave Earth. I understand re-entry speeds are over this as gravity assist accelerates the craft. I follow the solar near approach would gain from that masses gravity. So could one of you please just make a list.

mfumbesi
2007-Jul-31, 09:16 AM
Bad news.

EvilEye
2007-Jul-31, 10:38 AM
What technology are you referring to?

In Carl Sagan's series COSMOS he showed schematics for a proposed nuclear powered ship that would go near lightspeed. (This was in the 80's)

He said (and explained how) that it could actually be built NOW (then), and it would really work, but the sheer size, and cost would prohibit it from ever happening.


And it would have to be built in space.

The question was
I am curious as to how fast we can get something to move.

Van Rijn
2007-Jul-31, 11:43 AM
In Carl Sagan's series COSMOS he showed schematics for a proposed nuclear powered ship that would go near lightspeed. (This was in the 80's)

He said (and explained how) that it could actually be built NOW (then), and it would really work, but the sheer size, and cost would prohibit it from ever happening.


I don't recall him saying that, but if he did, he was wrong. Even a multistage fusion rocket that we couldn't possibly build today would be lucky to manage 10-20% of light speed. The only extreme nuclear concept that might be possible today is fission/fusion based Orion, but even that is questionable, and 1% of light would be extremely impressive with that technology.

neilzero
2007-Aug-10, 09:02 PM
I don't think the space shuttle has ever gone more than 30,000 miles per hour with respect to Earth's surface. According to another thread the New Horizons space probe went (will go?) several times that fast including several gravity assist manuvers. Travel in space at a thousandth of the speed of light or faster is largely untested, but we will likely have an ion engine (or something similar) reach one percent of the speed of light within the next 20 years.
With a significant pay load, such as a human; we may never reach 1% of c. Neil

Nereid
2007-Aug-10, 09:24 PM
What about things somewhat bigger than atomic nuclei, but smaller than spacecraft? And not launched into space, but shot from guns, of some kind or another, right here on Earth (although perhaps in a chamber pumped pretty much free of air)?

m1omg
2007-Aug-10, 10:06 PM
What about things somewhat bigger than atomic nuclei, but smaller than spacecraft? And not launched into space, but shot from guns, of some kind or another, right here on Earth (although perhaps in a chamber pumped pretty much free of air)?

Well I guess that these are bullets propelled to orbital velocities in hypervelocity impact chambers used for determining the impact of space debris of some size and velocity hitting a spacecraft are the fastest.Maybe the Z machine when it propells small plates to 30 km/s ; http://209.85.129.104/search?q=cache:gK4z_k4b-3MJ:flux.aps.org/meetings/YR03/SHOCK03/baps/abs/S430001.html+z+machine+30+km/s&hl=en&ct=clnk&cd=5&gl=sk .I do not know.

mugaliens
2007-Aug-13, 04:59 PM
Are our spacecraft moving at even a percentage of the speed of light?

Come on, now... Even I move at a percentage of the speed of light when riding my bike: 30 feet per second, which is 2.98686E-06% the speed of light. It can also be expressed as 0.000003%, or 3 one-millionths of a percent of the speed of ligth.

DyerWolf
2007-Aug-13, 06:28 PM
Come on, now... Even I move at a percentage of the speed of light when riding my bike: 30 feet per second, which is 2.98686E-06% the speed of light. It can also be expressed as 0.000003%, or 3 one-millionths of a percent of the speed of ligth.

Poor draftsmanship 'O Detailed One.' I grovel in the presence of your unfathomable mind...

I really wanted to learn whether any of our space probes have reached speeds faster than 3,000 km/s.









If I may be so bold: "3 one-millionths of a percent" is, nonetheless, still not 'a percentage'.:whistle:

:D

m1omg
2007-Aug-15, 12:38 PM
Poor draftsmanship 'O Detailed One.' I grovel in the presence of your unfathomable mind...

I really wanted to learn whether any of our space probes have reached speeds faster than 3,000 km/s.









If I may be so bold: "3 one-millionths of a percent" is, nonetheless, still not 'a percentage'.:whistle:

:D

New Horizons is gping the fastest.Around 16.5 km/s:sad:.

antoniseb
2007-Aug-15, 01:34 PM
New Horizons is gping the fastest.Around 16.5 km/s:sad:.
Did you read the other posts in this thread? Messenger is going much faster than New Horizons right now.

Rues
2008-Jan-25, 06:44 PM
Why not remove the burden of mass, attach nanorobotics to a partical of light an have a great trip?

antoniseb
2008-Jan-25, 07:00 PM
Why not remove the burden of mass, attach nanorobotics to a partical of light an have a great trip?
Welcome to the BAUT forum.

Good idea. Create a nanobot weighing perhaps 100,000,000 protons, and put it on a Solar Sail a few cm across made of Carbon nanotubes spaced five per micron, with a mass of about 10,000,000,000,000 protons. Total mass: 16 picograms. Hit it with the most intense laser that won't melt it, and let it fly.

astromark
2008-Jan-25, 09:30 PM
So... This microscopic space prob arrives at some far distant civilized outpost and...
gets eaten by a rodent.
Swallowed by a bird.
lost in the sand dunes.

What are you thinking..? If you make a space vessel so small as to attain near to light speed..,but can not actually do anything with it. Please explain where this might be a good idea..?

Rues
2008-Jan-25, 09:57 PM
Well,,, If a rodent ate my nanorobot, we would have to kill the rodent.

Rues
2008-Jan-25, 10:11 PM
Can not sophisticated robots replicate themselves in the millions, billions, trillions? Could robots of microscopic size build robots of average size? Really is there anything a robot could'nt do?

Van Rijn
2008-Jan-25, 10:24 PM
Can not sophisticated robots replicate themselves in the millions, billions, trillions?


It depends on your definition of "robot." Certainly, self replicating systems currently exist that can replicate themselves in the trillions under the right conditions. However, I suspect you're thinking of something a bit different. If you're talking about robotic systems that we build - not yet.



Could robots of microscopic size build robots of average size? Really is there anything a robot could'nt do?

They couldn't break physical law. Energy and material limitations are commonly ignored in stories about self replicating systems. Also, if we built self replicating systems (macro, micro or nano scale) we might well build in some limitations to go along with the practical limitations.

mugaliens
2008-Jan-25, 10:52 PM
Why limit the term "object" to spacecraft-sized? In your own home, every time you turn on a flashlight, you accelerate human-made objects (photons) to nearly the speed of light (attenuated only by the refractive index of our atmosphere).

dgavin
2008-Jan-27, 04:31 PM
With Ion propultion it should be possible to reach speeds near .35 light.

However it would take years of acceleration to reach that point, and would unly be usefull for interstellar probe, as you'd have the slow the thing down again. Which also require years of deceleration.

JanieBelle
2008-Jan-29, 12:31 AM
Dr. BA suggested to me that I ask here, so although I dread being skewered, here's the assist I need:

I'm currently writing a novel mocking the Intelligent Design Creationism Hoax and its perpetrators. It's set in the future. The plot requires interstellar space flight of human beings.

Now, I'm not looking for the magic and mystical warp drive, but I do need to make the drive work on principles that are at least plausible enough to encourage the suspension of disbelief. I was hoping you folks might help so I wouldn't wind up as a negative example on the pages of BadAstronomy. I'd really appreciate any assistance y'all could offer.

I like, and need for the novel, strong female characters, basically because there's nothing that will aggravate a fundy more than an overachieving girl.

To those ends, I'd like to base my fictional drive on the work of Dr. Lene Hau, and her work involving stopping a beam of light, changing into matter, and then releasing it from a point several nanometers away.

Here are the few relevant paragraphs in their current (albeit still rough in a literary sense as well as a science fiction sense) form:


Interstellar travel became possible because of a breakthrough in physics right around the turn of the millennium. A mere hundred years previous to that, a physicist named Einstein had shown mathematically that traveling faster than the speed of light was impossible. Even moving at that speed would make journeys to the stars extremely impractical, so a general shift in this branch of physics research took place. Instead of trying to break the light barrier, physicists began to look for ways around it. One such scientist, Dr. Lene Hau discovered that she could stop a beam of light in one place, change it into matter, hold it, then send it on its merry way beginning from an entirely different position a few nanometers away by using some arcane principle of Quantum Mechanics which I do not understand to this day. Once she had accomplished that, it just became a matter of two variables; scale and a placement of a receiver.



Even using her original method, there needed to be some sort of device at the receiving end, the point where the light picked up its journey again. That meant that if you wanted to use this technique to travel to the nearest star, you first still had to travel there conventionally, a trip taking thousands of years at that level of technology, to install the receiving device.



But then she and others built on that technology, and discovered that they could create a form of the receiving device by manipulating matter in one place and manipulating energy in another place some distance away. So by building a receiver in her lab, she could create one in the parking lot of her lab out of energy without ever leaving her office - or something like that. I'm a starship captain, not a physicist.



Massive advances in computer capacity and speed made just before the fall of the Republic allowed for calculating all the variables of any piece of matter, turning it into information embedded in a beam of energy, running it though Dr. Hau's device, and then in some other place extracting all the information necessary to reconstruct the original matter from the beam when it emerged.



While in theory this could be used to transport anything almost instantaneously from one point to any other point in the universe at will without ever needing a starship, the rise of the Pax crippled her research. Such absolute freedom of movement would have spelled the end of the Pax's control.



Part of the cat was already out of the bag however, and the Pax could not put it back. The research already in hand led to the first starships, and it is on these principles that the Hau drive still works. In layman's terms, the drive projects a receiver into empty space ahead of itself, turns itself into energy, transports itself, reconstructs itself, and then repeats thousands of times a second. In this way large distances can be covered by taking many little bites without running afoul of the universe's grand speed limit. The time it takes to cover a given amount of distance is only constrained by the speed of the computer running the drive and the distance it is able to project the receiver.

dgavin
2008-Jan-29, 01:19 AM
JanieBelle,

I could suggest you do a search on NASA's web site for Abercombie Warp Drive.

Its the only theoretical model of a FTL drive that could actually work with the physics we know today so far.

The problem with the drive you mentioned, is the transmision of energy. The energy would have to 'move' to the receving point and that would be constrined to the light speed limit.

Such a thing might be possible if you were making the recievers out of Quantum Entangled matter, but no ones managed to make Entangled matter very stable yet.

I'd say Ambercombies Warp Drive would be your best best.

JanieBelle
2008-Jan-29, 01:33 AM
Thanks for the direction.

The quantum entanglement thing is what I was shooting for, I just couldn't manage to pull the name out of my head. I'm brain fried at the moment from working at the novel so hard, I think.

I'll do a look see for the Abercrombie Warp Drive, and see if I can work with that.

JanieBelle
2008-Jan-29, 02:31 AM
Sorry, Double post, apparently.

JanieBelle
2008-Jan-29, 02:33 AM
Ok, I've searched the crap out of NASA's web site and I'm coming up blank. No Abercombie or Ambercrombie or Abercrombie (also no Fitch, just to be sure).

I did however come across a guy named Alcubierre:

Here’s the premise behind the Alcubierre "warp drive": Although Special Relativity forbids objects to move faster than light within spacetime, it is unknown how fast spacetime itself can move. To use an analogy, imagine you are on one of those moving sidewalks that can be found in some airports. The Alcubierre warp drive is like one of those moving sidewalks. Although there may be a limit to how fast one can walk across the floor (analogous to the light speed limit), what about if you are on a moving section of floor that moves faster than you can walk (analogous to a moving section of spacetime)? In the case of the Alcubierre warp drive, this moving section of spacetime is created by expanding spacetime behind the ship (analogous to where the sidewalk emerges from underneath the floor), and by contracting spacetime in front of the ship (analogous to where the sidewalk goes back into the floor). The idea of expanding spacetime is not new. Using the "Inflationary Universe" perspective, for example, it is thought that spacetime expanded faster than the speed of light during the early moments of the Big Bang. So if spacetime can expand faster than the speed of light during the Big Bang, why not for our warp drive? These theories are too new to have either been discounted or proven viable.
Any other sticky issues?

Yes... First, to create this effect, you’ll need a ring of negative energy wrapped around the ship, and lots of it too. It is still debated in physics whether negative energy can exist. Classical physics tends toward a "no," while quantum physics leans to a "maybe, yes." Second, you’ll need a way to control this effect to turn it on and off at will. This will be especially tricky since this warp effect is a separate effect from the ship. Third, all this assumes that this whole "warp" would indeed move faster than the speed of light. This is a big unknown. And fourth, if all the previous issues weren’t tough enough, these concepts evoke the same time-travel paradoxes as the wormhole concepts.
So although my original drive had the quantum entanglement issue, this guy's drive seems to have a whole lot more issues, like whether negative energy even exists, how to separate the effect from the ship, and whether it would even go faster than light.

Did I find the wrong guy? 'Cause that doesn't sound much like "a FTL drive that could actually work with the physics we know today so far".

I'll keep looking for variants of "Ambercombie" or "Abercombie" (the two spellings you gave me).

In the meantime, I'm still open to suggestions if anyone's got 'em.

Neverfly
2008-Jan-29, 02:41 AM
I've heard of AberCrombie- but it has nothing to do with FTL drives.

You got it when you said Alcubierre (http://en.wikipedia.org/wiki/Alcubierre_drive). That's the correct one.

I had thought you were kidding when you said abercrombie. I thought about posting a correction after you but... Didn't wnat to misinterpret the joke.:whistle: Oh well..

JanieBelle
2008-Jan-29, 03:05 AM
Thanks Neverfly. No blood, no foul. If nothing else, you saved me even more frustration and time in continuing to search.

It looks to me like I'd have to pull more crap out of thin air to make Alcubierrebercrombiewhatever's drive work than to make mine work.

FriedPhoton
2008-Jan-29, 03:06 AM
In Carl Sagan's series COSMOS he showed schematics for a proposed nuclear powered ship that would go near lightspeed. (This was in the 80's)

He said (and explained how) that it could actually be built NOW (then), and it would really work, but the sheer size, and cost would prohibit it from ever happening.


And it would have to be built in space.

The question was

Pulling my well-worn Cosmos book from my shelf and looking up in the index what I remember being called Orion, I find:

"Today we have preliminary designs for ships to take people to the stars. None of these spacecraft is imagined to leave the Earth directly. Rather, they are constructed in Earth orbit from where they are launched on their long interstellar journeys. One of them was called Project Orion after the constellation, a reminder that the ship's ultimate objective was the stars. Orion was designed to utilize explosions of hydrogen bombs, nuclear weapons, against an intertial plate, each explosion providing a kind of 'put-put,' a vast nuclear motorboat in space. Orion seems entirely practical from an engineering point of view. By its very nature it would have produced vast quantities of radioactive debris, but for conscientious mission profiles only in the emptiness of interplanetary or interstellar space. Orion was under serious development in the United States until the signing of the international treaty that forbids the detonation of nuclear weapons in space. This seems to me a great pity. The Orion starship is the best use of nuclear weapons I can think of."

- Carl Sagan, Cosmos, (c) 1980


Cosmos was one of my favorite shows when I was a kid. My dad gave the book to me as a Christmas present one year. And to think my ex-wife used to hate all my books and wondered why I kept them all. I'm going to go call her and let her know that even after 28 years a book can still come in handy! Apparently I've kept it all this time just for this post. :)

Neverfly
2008-Jan-29, 03:12 AM
Thanks Neverfly. No blood, no foul. If nothing else, you saved me even more frustration and time in continuing to search.

It looks to me like I'd have to pull more crap out of thin air to make Alcubierrebercrombiewhatever's drive work than to make mine work.

No problem - lesson learned to pip up sometimes.

However, the Alcubierre method is currently the "most viable" method. Even if you need a quantity of Unobtanium.

If you are looking to maintain Scientific Accuracy - that is the method you want to use.

JanieBelle
2008-Jan-29, 03:33 AM
Even if you need a quantity of Unobtanium.

I had to read that twice.

I thought, "hey, I don't remember no stinkin' elements called ... oh."

:lol:

Bearded One
2008-Jan-29, 03:52 AM
JanieBelle,

Sounds like you are trying to build a FTL transporter. You might not want to try so hard, the more detail you give the easier it is to derail it.

The sad reality is that there is no current path to FTL travel/communication. If there was NASA would be going full bore to develop it! Alcubierre's drive is based on a bunch of maybes, most of which conflict with other physics. Quantum entanglement isn't much help either I'm afraid. It's a bit like a moving shadow, it can be FTL, but you can't really communicate with it. Though; I suspect, you may have more wiggle room there than with Alcubierre.

I have no idea how string theory fits into FTL :confused:

If your goal is as you stated you might want to stick to more concrete and defendable science. Consider what elements your story needs, does it really need FTL and/or matter transportation? Maybe you just need people at another planet or star system? Is the means of people getting into the environment important or simply the environment they are in?

Just offering things to consider here, it's your story and only you know the plot :)

Neverfly
2008-Jan-29, 03:54 AM
Think FIREFLY!http://us.i1.yimg.com/us.yimg.com/i/mesg/emoticons7/4.gif

JanieBelle
2008-Jan-29, 04:29 AM
Well first, thanks for the continuing thoughts, I really do appreciate them.

I do need the FTL, as the underlying theme is the unchecked expansion of an Orwellian type empire, and most of the plot is hunt and chase.

I'd put off the details of the FTL drive thus far for reasons of flow, and I'm now at the point where I have to give some modicum of an explanation or ignore the point altogether. The original plan was actually to ignore the details, but as time went on I began to consider changing my mind for two reasons:

1. It began to feel like a cop-out. I felt that if I were to stand a chance of entertaining readers with any scientific literacy or any sci-fi experience, I was going to have to answer the inevitable question that would be nagging at them. "How'd she do that?"

2. Suppression of science by a ruling politico-religious body is a major part of the theme, and demonstrating the practical usefulness of science seems integral to contrasting the progress of science with the stagnation of theocracy.

As I mentioned, the drive doesn't have to necessarily be 100% feasible in reality, but again my novel, although as much social critique as science fiction, is geared toward the at-least-modestly-scientifically literate and so the drive should be plausible enough to be entertained and entertaining rather than detract from the story.

Now, all that said, I really, really liked the premise of my original idea both because the experiment which inspired it fascinates me and because that experiment was done by a woman, which serves to pour salt in the wound of the misogynistic bad guys.

Here's what I'm thinking at the moment. I can keep Dr. Hau's work in and use it for the transporter system (Yay!), and use whathisname's drive for the FTL. The major downside to this is that while I kind of had a layman's clue as to what Dr. Hau did, I'm really ignorant about the Abercrombieandfitch engine and the principles underlying it.

I'm all good in the paragraphs I quoted above from NASA right up to the part about the ring of negative energy. At that point, my eyes sort of rolled back in my head, and my tongue hung out and there might have been some unglamorous drooling involved. Complete. Mental. Shutdown.

(The twins paradox thing can kiss my butt. I'm not dealing with that at all.)

JanieBelle
2008-Jan-29, 04:32 AM
Think FIREFLY!http://us.i1.yimg.com/us.yimg.com/i/mesg/emoticons7/4.gif

I really LIKED Firefly, though I don't recall them talking about how the FTL drive worked before SOME JERK CANCELED IT!!!!111!!!!

I should have paid better attention to the details, I guess. I HATE when they cancel all the good shows, but mindless drivel goes on and on for years.

Neverfly
2008-Jan-29, 04:33 AM
Well first, thanks for the continuing thoughts, I really do appreciate them.

I do need the FTL, as the underlying theme is the unchecked expansion of an Orwellian type empire, and most of the plot is hunt and chase.

I'd put off the details of the FTL drive thus far for reasons of flow, and I'm now at the point where I have to give some modicum of an explanation or ignore the point altogether. The original plan was actually to ignore the details, but as time went on I began to consider changing my mind for two reasons:

1. It began to feel like a cop-out. I felt that if I were to stand a chance of entertaining readers with any scientific literacy or any sci-fi experience, I was going to have to answer the inevitable question that would be nagging at them. "How'd she do that?"

2. Suppression of science by a ruling politico-religious body is a major part of the theme, and demonstrating the practical usefulness of science seems integral to contrasting the progress of science with the stagnation of theocracy.

As I mentioned, the drive doesn't have to necessarily be 100% feasible in reality, but again my novel, although as much social critique as science fiction, is geared toward the at-least-modestly-scientifically literate and so the drive should be plausible enough to be entertained and entertaining rather than detract from the story.

Now, all that said, I really, really liked the premise of my original idea both because the experiment which inspired it fascinates me and because that experiment was done by a woman, which serves to pour salt in the wound of the misogynistic bad guys.

Here's what I'm thinking at the moment. I can keep Dr. Hau's work in and use it for the transporter system (Yay!), and use whathisname's drive for the FTL. The major downside to this is that while I kind of had a layman's clue as to what Dr. Hau did, I'm really ignorant about the Abercrombieandfitch engine and the principles underlying it.

I'm all good in the paragraphs I quoted above from NASA right up to the part about the ring of negative energy. At that point, my eyes sort of rolled back in my head, and my tongue hung out and there might have been some unglamorous drooling involved. Complete. Mental. Shutdown.

(The twins paradox thing can kiss my butt. I'm not dealing with that at all.)

If you have read Carl Sagan's "Contact" he struggled with a similar dilemma. He also chose the same route that you seem to have.

JanieBelle
2008-Jan-29, 04:57 AM
I am ashamed to admit that Contact is one of the very few movies I have seen but do not own the corresponding book. Although I remember that I enjoyed the movie, I don't recall much about it.

I'm not sure which dilemma (there are so many!) or which route you mean. About the twins paradox?

Neverfly
2008-Jan-29, 05:13 AM
I am ashamed to admit that Contact is one of the very few movies I have seen but do not own the corresponding book. Although I remember that I enjoyed the movie, I don't recall much about it.

I'm not sure which dilemma (there are so many!) or which route you mean. About the twins paradox?

About Faster than Light travel, and he chose to find the best applicable theory and explain it to the readers.
http://www.sff.net/people/brian_a_hopkins/ftl.htm

Carl Sagan asked some theoretical physicists for plausible methods of FTL travel when he was writing Contact. Among the team that worked on this problem was ...

JanieBelle
2008-Jan-29, 05:14 AM
My story including the twins paradox:

"There I was. (This kind of story always has to start with "there I was". It's a law.) Kate was chained to the wall in the dungeon and I had no key to free her.

So I hopped in my starship and made a quick run to Aldebaran, where I killed three alien seamonkeys to get to a trader who had a blaster for sale. Fortunately, he took my debit card, and I raced back to Kate.

I arrived back at earth the next day...

...to find the dust left over from Kate's body because she'd been dead for two thousand years."

What the heck kind of story is THAT?

JanieBelle
2008-Jan-29, 05:16 AM
About Faster than Light travel, and he chose to find the best applicable theory and explain it to the readers.
http://www.sff.net/people/brian_a_hopkins/ftl.htm

Well, I hate to be immodest, but great minds think alike...

:)

(OK, there's not a single modest bone in my body, but that's my story and I'm sticking to it.)

ASEI
2008-Jan-29, 05:17 AM
What technology are you referring to?

Why a massive self-burning blob of solid propellant, of course. Nevermind that the mass fraction for the payload versus propellant can only be expressed in large negative quadruple digit powers of ten. That's why no one can afford it. :-P

dgavin
2008-Jan-29, 06:13 AM
Janie,

Sorry about getting the name wriong on Alcubierre's Warp Drive. In my own defense I'm almost 43 and my brain is probably turning into mush.

You could invent a new type of drive system, such as one that changes the flow of time, such that a ship that moves at 20,000 miles per hour, moves through time also, such that a faster then light speed -effect- is achevied, even though nothing actually moved FTL. A drive like this could have some fun issues for a book, such as if the time drive is damaged, they could wind up in a repeating time loop, cease to exist if they violate Hakings CPC therory by traveling backwards in time, or being propelled backwards in time to the Big Bag and join that conflagration's energy, or something less dire such as arriving at your destiation as a baby when you had left at age of 30.

Could have a lot of fun with that.

As far as what powers it physics wise, could just say something like, "certain arrangements of the elementry time paticles, Chronoton's, allow for alteration of the flow of time in or around an object or ship."

JanieBelle
2008-Jan-29, 12:30 PM
That's OK dgavin. The effect wasn't terminal. :)

I'd be more confident in creating my own drive from whole cloth if I had a better handle on physics generally. For now I think I'm going to attempt to do something that at least has roots in currently known physics. That gives me a base from which to work, and I can ask questions and hit the Google mines.

I guess I should have started my own thread for this instead of hijacking this one. My apologies, I didn't think it would stray so far afield.

jotunrunner
2008-Apr-16, 05:25 AM
this is actually a subject which needs some consideration. in roughly one and one half million years, Gleise 710 (a star) will be close enough to affect our solar system with its gravity.
HR 8210 A is also due for a supernova event, and is close enough to really make life here very difficult if it does. this event is guesstimated as possibly as soon as only 10,000 years on the inside.
so we need to get moving.
Wolf is too old to be much help, and the Centauri suns might be extra tricky what with their gravitational relationship.
seti is a good target, and Epsilon Eridani is also a good candidate, being young, of a similar type of star, and a mere 10.5 LY away.
the problem is mathy.
assuming a large, orbital construction equipped with strong rocket boost to start, a nice little sequence of gravity boost from sun, gas giants, etc.
then a good sized ion engine for a nice lon peristant acceleration (AND an equal amount of brake thrust. . . how fast do you suppose we could get, say, a shuttle sized object going?
the optimal acceleration to maintain is, of course, 1g. that way, all the time spent in space, theres an equivalent to gravity. turn the spacegraft around for braking, and you get gravity for the second half of the trip.
nice, long trip.
the other half of the problem is prolonging or preserving the life of any human to go along.
near light speed? i'd be happy with .001e. pretty fast. a thousand years to Epsilon eridani.
best we dont wait til the last minute.

jotunrunner
2008-Apr-16, 05:46 AM
after posting above, i went back and read the posts about sailing nanobots.
on to something there, though solar sails have the same problem as ambient radio signals. they dont really make it past the heliosphere.
ion engines seem the way to go, though a sail would be a great idea for getting it a little extra boost on its way. every littly bit would help.
heres the trick, though, once it got there: (wherever).
our machine would have to have, instead of the bulky systems required to gather and transmit information, only the programming and apparatus needed to find raw materials and manufacture such apparatus.
most stars that are of any real use to us are such because they contain similar materials. silicon, iron, hydrogen, and so on. most places we look, we are likely to find huge portions of this stuff floating about in deep orbits (vide, asteroid belt, kuiper belt, et al)
so perhaps simple machines capable of building slightly more complex machines (lenses, sensors, radio trancievers) could be sent to build from native materials the first steps toward human explaoration. for getting there fast, smaller is better.
the story im working on here, has no FTL. we have what we have, and have to use it to split. playing around with ideas on the fictional side, like, graviton manipulation, nearlight or lightspeed, im steering clear of.
but in the vein of mocking the creationists, a synopsis:
at a distant, but very young star, selected by type, mass, and materials, a single pilot, using some heavy-duty trigonometry and a few clever pushes and pulls, manages to manipulate the protoplanetary material of the system to influence the aggregation of a new and habitable earthlike planet.
the process takes a couple billion years, of course, but our pilot, spending most of this trip encased and preserved, spends seven days pulling this off.
:D

dnj123
2008-Apr-21, 06:46 PM
There's also the issue of colliding with unaccounted meteriods and larger objects; it could be catastrophic .

stock
2009-Dec-29, 01:15 PM
guys, i gotta tell you. The ion drive leaves giant trail, and accelerates too, but too slowly!
And about speed records, that can't be easier! (from nasa's point of view), they gotta invest couple of bucks ... like it's a problem to them. That wouldn't be a big project. It'd be almost routine, only difference is that they would have to make a material extremely resistant to close-up Sun's heat. Which I don't doubt, they already have. So, they launch the probe "speeder I" towards the sun and make it go in very low orbit around the sun. And circle, and circle, and circle... ... ... till it finally melts (getting it home instead of letting it melt is completely another story (and a couple of bucks more)). When it melts, that would be it. At least we'd give Sun about 1 second longer life when "speeder I" parts crash on it. The point is that orbiting. It would use Sun's gravity to 'get' itself into it's orbit, and with such a great mass and very low orbiting around that great mass, it'd require a massive amounts of speed. mph, kmph, m/s, ly/?, who knows...

WayneFrancis
2009-Dec-30, 02:38 AM
Ummm ok, dead post dug up why?

Andrew D
2010-Jan-03, 03:43 PM
What about things somewhat bigger than atomic nuclei, but smaller than spacecraft? And not launched into space, but shot from guns, of some kind or another, right here on Earth (although perhaps in a chamber pumped pretty much free of air)?


http://en.wikipedia.org/wiki/Space_cannon

Rhadamant
2010-Jan-22, 07:39 PM
With a significant pay load, such as a human; we may never reach 1% of c. Neil

Our solar system moves at 885,139 kilometers per second.

The earth revolves around the sun at 30 kilometers per second.

And you know one of these days we will send a probe into a black hole, and at some point that probe will be moving FASTER than the speed of light (granted it won't really be a probe at that point).

BlueEyedBoyMrDeath
2014-Apr-16, 04:21 AM
It all depends on how big of an object you want to accelerate. In particle accelerators, we get subatomic particles up to significant fractions of the speed of light. As far as objects big enough to feel/touch, the fastest I am aware of were the Helios probes, which made extremely close passes to the sun, and reached speeds upwards of 150,000 mph (roughly 250,000 kph).

However, you question relates to missions to the outer Solar System, where the extreme Solar gravitational forces that accelerated the Helios probes are not available. The best example of a high-speed outbound probe is New Horizons, which is currently traveling at a velocity of about 54,000 mph (24 km/s) with respect to the Sun. Its speed will vary on its trip to the outer Solar system, but it will take roughly 10 years to reach Pluto.

With larger rockets and/or a more ideal planetary alignment for multiple gravitational assists, it would be theoretically possible to make that trip faster, but not by more than a couple of years.

Regardless, you will never see planetary probes or inter-planetary spacecraft within the Solar system travelling much faster than this simply because of the extreme amounts of energy required to slow back down when you reach your destination. If a probe passed Pluto at any significant fraction of the speed of light, you would have very little time to collect any data. As it is, at the speed of New Horizons, the project scientists are going to really have to hustle during the few months when New Horizons is close enough to the Pluto system to get good pictures/measurements.

Thanks for your response. It was a complex question about a pretty esoteric topic, and you pretty much hit the nail on the head.