Asteroid Ships

[victory143]

Say it's the year 5 Billion and the Sun is dying, expanding and close to the earth, could the last of Humanity turn an asteroid in to a spaceship? For example, we could mine out the inside of Astroid Vesta and colonise the 500 Km space inside.

[Moon Goddess]

I'm not sure how gravity would work on the inside of a hollowed out asteroid.

[Ralathon]

Say it's the year 5 Billion and the Sun is dying, expanding and close to the earth, could the last of Humanity turn an asteroid in to a spaceship? For example, we could mine out the inside of Astroid Vesta and colonise the 500 Km space inside.

In 5 billion years we're either dead or practically gods. Look at the technological progress and extrapolate over 5 billion years. Building an asteroid ship would be childs play.

I'm not sure how gravity would work on the inside of a hollowed out asteroid.

Shell theorem says that you'll be in 0G.

[Nuke]

what i would do use use an ice dwarf. i would use the ice as fuel for a nuclear water (or ammonia, or whatever) rocket, or perhaps some kind of fusion-electric. the important thing is that melted ice is either used as the propellant, or is used to make the propellant (which could be hydrogen or hydrazine or something). i imagine fields of engines all pointed skyward surrounded by open pit mines gathering ice to feed the thruster farms. the thrusters would be mounted on treads so they can be moved as areas are mined out, and to redistribute thrust as needed. any non-ice materials can be utilized by the inhabitants, or simply thrown overboard to lessen the "ship"'s mass.

habitation would be in underground centrifuges, as any gravity will be too small to be useful. depending on how much gravity is available, you may need a more conic centrifuge to compensate. i imagine these being constructed in deep open pits (perhaps retired mines), and then capped over with a dome of reinforced ice, for radiation shielding.

Edited March 7, 2014 by Nuke

[Dispatcher]

Yes, it might be done.

[falofonos]

Find a nice homogenous nickel iron asteroid, drill into the center of it and hollow out a void in the middle. fill the void with ice. Boost the rock into a close solar periaps orbit then start it spinning. It passes close to the sun, the iron and nickel melt a little, the ice vaporises and in theory (if you get the math correct) your chosen rock balloons out to create an hollow shell which cools off and solidifies on its' trip back to earth orbit. A bit of engineering later and you have a nice spin able habitat or generation ship hull.

I think this was suggested by Larry Niven

[Camacha]

I am not sure why you would want to do that. It will pose difficulties that a normal big spaceship will not have, not to mention that you carry around a lot of mostly useless mass.

Maybe that you can use one as a micrometeorite shield for high speed interstellar travel, though I guess that things like a laser grid are more useful.

[Tex]

Then, of course, there's always the option of converting a metal-rich asteriod into a spacecraft using conventional methods. Not technically far-fetched!

As for the inside of an asteroid, eh- only maybe. It would require unrealistic supports to hold up the integrity of the rocky exterior of such a spacecraft, not to mention the asteroid will be more than likely uneven, so it would be extremely difficult to balance any engines you put on so they have even thrust.

Final verdict: possible but veeeeery hard!

[Sirrobert]

By that time, humanity is either gone, or praticly teleporting between star systems. I don't think we'll have to worry about that

[Dust]

Find a nice homogenous nickel iron asteroid, drill into the center of it and hollow out a void in the middle. fill the void with ice. Boost the rock into a close solar periaps orbit then start it spinning. It passes close to the sun, the iron and nickel melt a little, the ice vaporises and in theory (if you get the math correct) your chosen rock balloons out to create an hollow shell which cools off and solidifies on its' trip back to earth orbit. A bit of engineering later and you have a nice spin able habitat or generation ship hull.

I think this was suggested by Larry Niven

That was Greg Bear's novel Eon (http://en.wikipedia.org/wiki/Eon_%28novel%29), one of the many, many books I read in my dad's sci-fi collection.

[andrewas]

Nope, Thistledown was, externally, virtually identical to Juno, it wasn't melted and expanded as Niven proposes.

[Everten P.]

Cool idea but you have to realize that 1. The asteroid and kupler belts don't have enough asteroids to fill up the earth 2. We would be technical gods and it would be as easy as breathing.

[Red Iron Crown]

Nope, Thistledown was, externally, virtually identical to Juno, it wasn't melted and expanded as Niven proposes.

It had a rather...unique interior if I recall correctly.

[meve12]

Find a nice homogenous nickel iron asteroid, drill into the center of it and hollow out a void in the middle. fill the void with ice. Boost the rock into a close solar periaps orbit then start it spinning. It passes close to the sun, the iron and nickel melt a little, the ice vaporises and in theory (if you get the math correct) your chosen rock balloons out to create an hollow shell which cools off and solidifies on its' trip back to earth orbit. A bit of engineering later and you have a nice spin able habitat or generation ship hull.

I think this was suggested by Larry Niven

It was.

If you're using a thruster with any thrust above .1 G, you might want to 'forge' this under thrust and while spinning around the axis of thrust, making it more egg shaped. Better effective armor along the flight path, and the 'bottom' of the egg will have artificial gravity balanced between centrifugal force and direction of thrust.

...You know what? We're not thinking large enough. Make a fusion engine out of Saturn.(There's plenty of He3 for ignition.)

Specifically, we coat the top of Saturn's atmosphere with a superconductor 'net' that sticks out in a nozzle shape at one point, probably North or South. Use some other power source to boost/provoke Saturn's interior magnetic fields and cause an out-gas of He3 gas into the nozzle, where we fuse it. The magnetic flux from the resultant plasma might be harvested for energy to boost the magnetic field and keep feeding He3 into our fusion torch.

Said magnetic field would also act as radiation protection and propulsion via magsails for ships near Saturn.

It might also be possible to cause Saturn's atmosphere to lase if we need a weapon/ debris defense. Otherwise we suspend lots of mag-sail craft way out in front, so they can catch and redirect or capture debris.

We might want a 'mouth' of superconductor sticking out the front to act as a planetary size ramscoop(Need not be large; we can dive near a star and grab H2 fuel from the solar wind). This won't replenish our He3 all that well, but would enable use of more energetic D2/He3 fusion, allowing us to stretch our He3 supplies.

Otherwise we'll need a fairly close destination.

My electromagnetic field theory is nonexistent, so no idea if this is at all possible.

If it works, we scoop up Earth and possibly Venus with Saturn's gravity on our way out, along with as many asteroids as we can. We keep all this on a orbit perpendicular to thrust, otherwise we end up frying our cargo.

We need the asteroids for new construction, materials and replenishing volatiles.

We cause a day-night cycle by rotating the planets around Saturn's axis of rotation, so that the torch acts as a sun.

We can erect other superconductor nets to control Earth's and Venus's magnetic fields so we can maintain our attitude/altitude.

[Sirrobert]

snip

As impossible as that sounds, I do actually believe that by the year 5billion we'll be able to do something like that

[randomness5555]

Sure you could. You'd build it out of the material you mine out, probably with it ending up far bigger than it started out. You'd be able to grow food and trees (for Oxygen) in domes on the outside, live on the inside and put engines on it for propulsion. I know most asteroids are almost solid metal but it's pretty reasonable to assume we'd be able to mine it by then.

[jwenting]

Something akin to a fleet of Rama like ships would be much more appropriate.

[andrewas]

Another gas-giant moving scheme:

http://www.schlockmercenary.com/2003-08-03

[Legendary Emu]

That's no asteroid. It's a spaceship!

[meve12]

Another gas-giant moving scheme:

http://www.schlockmercenary.com/2003-08-03

That's a cheaper way to do it, actually.

Though wouldn't the thrusting end have to stick out very far? Otherwise you push atmosphere out along with the plasma thrust.

[andrewas]

Yes, but if you can build things on that scale at all then extending it that shouldn't be a problem. I'd be more concerned about having to waste half your fuel on the lifting drive, but then it might be possible to just anchor it in the core of the planet directly.

[Ralathon]

Yes, but if you can build things on that scale at all then extending it that shouldn't be a problem. I'd be more concerned about having to waste half your fuel on the lifting drive, but then it might be possible to just anchor it in the core of the planet directly.

I'd be more worried about the compressive strengths. That setup involves a long structure under heavy pressure. It is going to snap like a string of unboiled spaghetti.

You can always get more fuel from the atmosphere, you can't do that to reinforce your ship.

[MrZayas1]

Well, the only problem with colonizing an asteroid, is that gravity would be minimal, if any at all, and you wouldn't be able to predict their paths very easily, unless you know they are in the asteroid belt or the kuiper belt. And plus that would kinda be like a big floating town in space if i had to guess, where you know if you want to go to a friend's house you can just put your space clothes on and float to their house, if you miss, RCS backpacks FTW! But what that would be helpful for is that the asteroid would be a nice radiation sheild for you because in space, there is no atmosphere to protect you from the cosmic and radioactive waves in space! And mining asteroids in higher portions of the belt would be profitable.

I'd imagine that building rockets would be kinda difficult though, as the amount of fuel in space is limited, and most rocket fuels that we use are liquids, so planetary bases would be a must whether or not we move to asteroid belts or not. Many of the chemicals that we use in life would also be scarce in space, making the household items industry profitable, also people need a way to travel, so I could definitely imagine shuttles from maybe one end of the belt to another in a couple hours ride. So indeed, it would be like living on Earth, but we would be able to live in many different orientations, and conserve alot of space. But resources will be limited to planets, but I really do think that life in an asteroid belt would be pretty cool!

Hope this solves some issues and calms your curious mind

[victory143]

Yes, I think that this might not be a problem in the future...

[Nuke]

anyone whos ridden on the gravitron knows how to solve that problem.