Interstellar space travel

[Cabal]

Saw a documentary on Project Orion a couple of nights ago and it got me thinking about different methods of rocket propulsion, specifically over distances longer than our solar system - figured I'd start another physicsy thread.

Here's the two most interesting methods that I know of:

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

Bussard proposed a ramjet variant of a fusion rocket capable of fast interstellar spaceflight, using enormous electro-magnetic fields (ranging from kilometers to many thousands of kilometers in diameter) as a ram scoop to collect and compress hydrogen from the interstellar medium. High speed forces the reactive mass into a progressively constricted magnetic field, compressing it until thermonuclear fusion occurs. The magnetic field then directs the energy as rocket exhaust opposite to the intended direction of travel, thereby accelerating the vessel.

And a slightly more 50's solution, although I agree with Carl Sagan that it's a very practical way of decommissioning all those unnecessary nuclear weapons :

Project Orion (nuclear propulsion) - Wikipedia, the free encyclopedia

Project Orion was the first engineering design study of a spacecraft powered by nuclear pulse propulsion, an idea proposed first by Stanisław Ulam during 1947. The project, initiated in 1958, envisioned the explosion of atomic bombs behind the craft and was led by Ted Taylor at General Atomics and physicist Freeman Dyson, who at Taylor's request took a year away from the Institute for Advanced Study in Princeton to work on the project.

By using energetic nuclear power, the Orion concept offered high thrust and specific impulse at the same time; the optimum combination for spacecraft propulsion. As a qualitative comparison, traditional chemical rockets (the Moon-class Saturn V or the Space Shuttle being prime examples) provide (rather) high thrust, but low specific impulse, whereas ion engines do the opposite. Orion would have offered performance greater than the most advanced conventional or nuclear rocket engines now being studied. Cheap interplanetary travel was the goal of the Orion Project. Its supporters felt that it had potential for space travel, but it lost political approval because of concerns with fallout from its propulsion. The Partial Test Ban Treaty of 1963 is generally acknowledged to have ended the project.

Discuss.

Disclaimer: This is a thread for the joys of scientific discussion, spacefaring and lulz. Anyone preaching or engaging in my-theory-is-better-than-your-theory member-waving competitions will be forcibly ejected from the thread in a barrage of scorn and off-topic reports. Kthx.

 

[Legion.As.One]

as a sci-fi, astro-loving, alien-aweing schoolkid, I can't wait!
I'm placing bets on the fusion rocket. The ITER in Europe is only the beginning of the use of nuclear fusion to achieve our goals. 1st step: Fusion reactor for clean energy, 2nd step: creating a fusion rocket!

Although, I always like the idea of using artificial wormholes for space travel...

 

[Cabal]

as a sci-fi, astro-loving, alien-aweing schoolkid, I can't wait!

Honestly, I'd "settle" for some the places in the solar system, a fly-by tour of Io or Titan would be amazing. As for actual touchdowns, I think I'd quite like to go somewhere like Triton - nevermind somewhere outside this system....

I'm placing bets on the fusion rocket. The ITER in Europe is only the beginning of the use of nuclear fusion to achieve our goals. 1st step: Fusion reactor for clean energy, 2nd step: creating a fusion rocket!

Yeah, although it might be hard scavenging for fuel, at least the Bussard ramjet has the option of obtaining new fuel from the resources available in space, whereas the Orion rocket is heavily dependent on fissile material but Lord knows we have enough of that here....

Although, I always like the idea of using artificial wormholes for space travel...

It would be cool to do, but immensely hard to pull off (assuming it's possible, I've no idea if it is or isn't). I suspect the amounts of mass needed would make it rather impractical, not only logistically but also for the fact that even when it's made you can't move the endpoints very easily. But maybe they will be the freeways of the future, who knows.

 

[Legion.As.One]

Honestly, I'd "settle" for some the places in the solar system, a fly-by tour of Io or Titan would be amazing. As for actual touchdowns, I think I'd quite like to go somewhere like Triton - nevermind somewhere outside this system....

That would be quite a sight, just seeing the earth from space would be extrordinary.

maybe they will be the freeways of the future, who knows.

One can only hope

Do you have any other material on interstellar travel? As you can see, find it totally transfixing.

 

[AV1611VET]

Saw a documentary on Project Orion a couple of nights ago and it got me thinking about different methods of rocket propulsion, specifically over distances longer than our solar system - figured I'd start another physicsy thread.

I would say the method of choice right now for interstellar travel is either Divine Speed or what we would call a Wormhole.

My vote is wormhole.

The inhabitants of Babel seem to be privy to a wormhole (or wormhole technology), Jacob's Ladder seems to be a wormhole, as do sound waves going from Egypt to Heaven in real time.

The Apostle Philip was teleported to Azotus (Ashdod) from somewhere south of Jerusalem.

But since this thread is more about [manmade] propulsion, I'll leave it to scientists to try and match Godspeed.

 

[AV1611VET]

Honestly, I'd "settle" for some the places in the solar system, a fly-by tour of Io or Titan would be amazing.

Swedenborg thought so too.

 

[TemperateSeaIsland]

I doubt the speeds needed for intersellar travel within a human lifetime is technologically possible. The energy requirements are extraordanary and the ship should it reach even low relativistic speeds would be subject to a large amount of damage due to particle impacts from the stellar medium.

I'd go for long term colonization such as generational ships or maybe slightly more exotic Von Neumann replicators producing humans "synthetically" once they find/terraform a suitable home.

 

[Cabal]

I would say the method of choice right now for interstellar travel is either Divine Speed or what we would call a Wormhole.

My vote is wormhole.

The inhabitants of Babel seem to be privy to a wormhole (or wormhole technology), Jacob's Ladder seems to be a wormhole, as do sound waves going from Egypt to Heaven in real time.

The Apostle Philip was teleported to Azotus (Ashdod) from somewhere south of Jerusalem.

But since this thread is more about [manmade] propulsion, I'll leave it to scientists to try and match Godspeed.

Hey, I'd be all for it if God did this stuff on demand on a commercial scale, but somehow I expect he won't.

Wish there was more teleportation in the Bible though, it's usually entertaining.

 

[teddyv]

Has there been any further development of ion engines. From what I recall they can run continuously and are reliable, although acceleration is slow, but over enough time could move something at high speeds. Coupled with planetary slingshots, it might be feasible.

I don't see any interstellar travel in the near future. I think we will see a revisit to the moon and an attempt on Mars though in the nearish future (say next 20 years).

 

[AV1611VET]

Hey, I'd be all for it if God did this stuff on demand on a commercial scale, but somehow I expect he won't.

Interesting word choice --- your suspicions are well-founded.

 

[Cabal]

I doubt the speeds needed for intersellar travel within a human lifetime is technologically possible. The energy requirements are extraordanary and the ship should it reach even low relativistic speeds would be subject to a large amount of damage due to particle impacts from the stellar medium.

Think the Bussard ramjet incorporates some sort of scoop for obtaining ISM safely. Surely something that could ionise it and control the flow might make things a bit safer....

I'd go for long term colonization such as generational ships or maybe slightly more exotic Von Neumann replicators producing humans "synthetically" once they find/terraform a suitable home.

Eh, as long as they can clone me!

 

[Cabal]

That would be quite a sight, just seeing the earth from space would be extrordinary.


One can only hope [/COLOR]

Do you have any other material on interstellar travel? As you can see, find it totally transfixing.

Can't say I do - I'm trying to find George Dyson's book on Project Orion but it seems to be out of print *rage*

In the mean time, there's a great hard sci-fi novel called Tau Zero which is about the crew of a Bussard Ramjet, it's really cool.

 

[Cabal]

Interesting word choice --- your suspicions are well-founded.

Yes, just like how God isn't exactly going to teleport a billion or so commuters to work each morning, we have mass transit for that.

 

[Pwnzerfaust]

Interstellar travel is quite interesting to me. I wonder if a way to bypass the speed of light will ever be discovered somehow. Maybe by creating temporary wormholes to the destination or something like that.

I think the best realistically feasible way to go about it would be generation ships or, if suspended animation is ever realized, sleeper ships. Which is kinda the only two options, I suppose... Oh well. Shame I won't be alive to see it.

 

[Kharak]

Rockets are all fine and well until you reach the problem of acceleration. Well in theory: The fastest manner in which to reach point 'B' would be to utilize incessant acceleration until the halfway point is reach and deceleration is commenced or a gravity/aerobraking maneuver is performed. Both of these seem, erm, unpleasant to say the least if you are exceeding 1G (something tackled in the CoDominion novels).

This problem of acceleration is especially troublesome if you get into larger vessels. Say: O'Neill cylinders with engines (unless you like uber-seasickness). 'Coasting' to point B after a survivable thrust period is fine and well, but this would take up more time than anything else. The most practical means for transit may very well be just shooting shuttles of a sort with rail guns from point 'A' to a receiving net within point 'B'. Though that would be boring and involves classical physics only.

Alternatively, someone could invent hypersleep. Nothing to see between planets anyway. Unless you like going insane while pondering the vastness of space and wish to become a Reaver.

 

[laconicstudent]

Interesting word choice --- your suspicions are well-founded.

Then why, given that view, are you deliberately attempting to derail a discussion of commercial propulsion technologies into a discussion on God?

 

[TheReasoner]

Know I'm arriving late this thread, but have you considered matter/antimatter propulsion or the Alcubierre drive? The latter provides an interesting theoretical FTL drive.

 

[LordTimothytheWise]

How about Solar Sails for interstellar travel?

use the light from the home star to accelerate. The ship would first orbit continuously away around the home star until the appropriate starting velocity is reached, then the ship would begin its trip away from the system using the light from the star to keep accelerating. Once it was too far away from the star to keep using its light the ship would still continue on its journey using the physics of Newton's Laws of Motion that a moving object will continue at the same velocity unless a force acts upon it. That opposite force would be the target star which when the ship approaches it, would turn the sails toward it and begin to orbit inward to decellerate. Additional forward and reverse thrust could be achieved with more conventional means of propulsion such as rockets.

 

[Pwnzerfaust]

Know I'm arriving late this thread, but have you considered matter/antimatter propulsion or the Alcubierre drive? The latter provides an interesting theoretical FTL drive.

Maybe I remember incorrectly, but wasn't there some math done on how much energy would be required for that, and it was something like converting the mass of Jupiter into energy? I'm not sure, but I heard the energy requirements were infeasible.

 

[Michael]

Saw a documentary on Project Orion a couple of nights ago and it got me thinking about different methods of rocket propulsion, specifically over distances longer than our solar system - figured I'd start another physicsy thread.

Here's the two most interesting methods that I know of:

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

That one seems like the most feasible option, particularly when combined with these types of technologies:

Backyard reactors? Firms shrink the nukes. | csmonitor.com
A real-life ‘Star Trek’ deflector shield - Space.com- msnbc.com

I'm a big fan of EM propulsion systems and the idea of scooping up material to use as fuel is simply "fascinating".