It's off to Zeta Zkribbler VII

[Verto]

Science fiction is so much more fun than reality All those restrictions

[-Jrabbit]

We can overcome the time problem by incorporating a flux capacitor.
Can the sun provide 2.3 gigawatts of power?

[Whoha]

We probably can't colonize it for a long while(travel time excluded of course).

[DRoseDARs]

Barring both faster-than-light drives that could get us there in a matter of days/weeks/months (1) and some kind of suspended animation technology, you'd have to build what's called a generational ship. Excavate the core of a decent-sized, solid asteroid, fill it with some kind of habitable environment (2) and put a conventional engine (re:non-exotic Newtonian drives ... as in Sir Issac Newton and his Laws of Physics) on both ends (3) to speed it up and slow it down. Given the size of the asteroid, you could probably store enough fuel to do both, but you'd also want to utilize various gravity wells to pick up (or bleed off) additional speed (4). Depending on the size of the livable space inside the asteroid, the sustainable crops and their edible food output, and our ability to make this a self-contained stable ecosystem (5), we ought to be able to fit a few dozen families inside with room to grow over a generation or three (20-60 years). Assuming a very generous idea that we can accelerate the ship to 1/4th of the speed of light (6) it will take approximately 30 years to get there, plenty of time to have additional family members born, educated and reach adulthood by the time the ship gets to the destination planet.

(1) Basically, a journey of less than a year. Ocean voyages have gone longer, but this is space we're talking about. No safe harbors between here and there...
(2) Rotating the asteroid on a single axis parallel to the direction of travel will provide a stable faux-gravitational environment for anything attached to the internal wall of the excavated cavern.
(3) Why not just rotate the asteroid on an axis and use a single engine like we do with the space shuttle? Because it will take a lot of energy to do that and the asteroid might already be strained by rotational forces if you're providing faux-gravity. Also, rotating on an additional axis will mess with the internal environment that depends on steady faux-gravitational forces.
(4) The Earth, Venus, Sol and any of the gas giants, in addition to your destination planet, any gas giants and their sun (or suns) will do nicely. Also: Generational ship made from a hollowed-out asteroid + Aerobraking = Disaster waiting to happen. Just don't do it.
(5) This has yet to be comfortably achieved after several well-publicized attempts.
(6) The reality is that accelerating a mass the size of an asteroid, even hollowed out, would require a massive amount of energy. Accelerating the asteroid to 1/4th the speed of light would probably shatter it in the process. The speed of light in a vacuum is ~186,000 miles per second while the fastest object we've ever made traveled at ~43 miles per second. Needless to say, at that speed it would take a verrrry long time to go seven lightyears.

If we're serious about getting Humans anywhere in the galaxy outside of our own planetary system without exotic drives or wormholes and without energy-intensive (and as-yet non-existent) suspended animation technologies, then large generational ships accelerated somehow safely to at least decent fractions of the speed of light are really the only way of doing that.

[Addled Platypus]

get some spice, call the big ugly

bam

you are there

simple

[Drake Tungsten]

Can the sun provide 2.3 gigawatts of power?

1.21 gigawatts...

[Sandman]

Urgh, this thread has shaken my faith in Apolyton's nerdiness. Generational ships? Solar power being useful outside of Jupiter's orbit? Puh-leez.

Freeze around 100 colonists. Scientists refrigerated a dog for seven minutes a few months ago, seems reasonable that some sort of 'coldsleep' may be feasible. You need to drain the blood and replace it with cryogenic fluid, and its dangerous and messy, but probably doable. Easier than farting around with artificial ecosystems or the psychological ghastliness of generational ships, at least.

Avoid inbreeding by taking a big store of eggs and sperm with the colonists.

Build a huge starship in orbit with aid of a space elevator. Difficult, but probably the only way. The starship will require many complex components that can only be sourced from Earth. Those who think 'mining' asteroids for 'ore' can supply the building materials are playing too many computer games.

Propulsion is the difficult one. Something involving fusion probably. Or ion thrusters (used on a few recent space missions). Maybe use fusion for acceleration and ion thrusters for deceleration?

[Spiffor]

Originally posted by Sandman
Avoid inbreeding by taking a big store of eggs and sperm with the colonists.

How didn't I think of that?

We should be having artificial wombs in some years/decades. Instead of manning the ship with hundreds of colonists, it's much easier to man it with only a few professionals, and to start sprouting population artificially upon arrival. The ship won't have to be nearly as big as an actual colonization ship.

[Kuciwalker]

There's something fundamentally masturbatory about sending off a ship with no people, just eggs an sperm.

[DRoseDARs]

@Sandman, Spiffor

I already thought of that, but this thread was supposed to be within the realm of reality. Cryogenics is not near a workable technology yet, neither are the advanced robotics necessary to maintain a cloning system sans Human operators. As for having a skeleton crew instead of robots, because of their limited numbers and the extended nature of the mission they'd likely become psychologically unstable after the first few years. I can't imagine them be able to handle seeing the same dozen or so faces for 30 years again assuming 1/4th c speed (though probably be much slower and much longer)...

Think of the generational ship as a small village, complete with adults, children, newborns and grandparents (perhaps even older generations if the voyage is long enough). Seems to me small villages have worked just fine since the dawn of Human civilization, but that's just fact so what do I know ... besides recorded history? Anyway, once they arrive at the planet, they'll already have the basic infrastructure for their colony setup inside the asteroid (because they've had a few decades en route to figure out what works and what doesn't); they just need to disassemble the buildings and reassemble them on the surface of the planet instead of starting from scratch like the other scenarios call for.

[Sandman]

Is hollowing out asteroids within the realm of reality? I admit that it's one of my most hated sci-fi tropes.

[Kuciwalker]

Is hollowing out asteroids within the realm of reality?

Easily.

[Sandman]

How?

[LordShiva]

Zeta Zkribbler

Zeta-Jones

[Kuciwalker]

Originally posted by Sandman
How?

If you can get any meaningful amount of men and equipment to the asteroid (kind of a prerequisite for getting to another star...) then you just mine it out. Chuck the extra rock randomly into space, into a bin, whatever...