Sat 15 Aug, 2015 09:32 am
Sci-fi occasionally utilizes the actual ins and outs required for human travel, but generally not. So most people think we just need to go really fast.
Unfortunately, there's no fast fast enough to travel interstellar distances. Velocity maxxes out at light-speed which given the distances involved isn't fast enough for humans passengers to get anywhere in a reasonable amount of time (before food, water, air run out, and crews go insane, or die from old age.)
Some things needed:
- suspended animation, or reduced at the very least to conserve, air, food, water, and prevent crews going nuts, and dying from old age
- "force fields" to block radiation and micrometeor impacts. In Star Trek it's called 'navigational deflectors.' When not in warp, where your moving space but technically not the ship, you're going fast enough that a grain of sand can have the impact of a cruise missle so you need some way to protect yourself from hitting things too small to detect. Also need radiation shielding to protect the crew of sensitive electronics from radiation. On Earth, we're protected, away from the Earth there's no protection at all.
- warp drive like propulsion. Nearest star to Earth on the space shuttle (for humorous illustration) would take about 26,000 years to reach (at 25,000mph.) And even at lightspeed, over 4 years. (though due to relativistic time dilation, less.) Though of course at relativistic velocities, hit the perverbial grain of sand and you're done. So you need to move space, not the ship.
- lots of air, food, and water for the crew. More in case you don't find planets capable of supporting our life form. Will need some kind of artifical gravity as well or reductions in bone density on the astronauts will render them physically incapable of disembarking once they arrive somewhere. The human animal is not evolved to do well in microgravity. Too long and it kills us.
- and of course you need most of all a destination. No point going to a star system with no planets like. Nor a point going to a planet not capable of supporting life. As yet, we haven't found an exosolar planet capable of supporting human life (or if we have they're keeping it under wraps.) Can imagine such a discovery would be classified since if there are other 'human friendly' planets known, we'd be less likely to protect this one.
We need a hollow asteroid, some momentum, and time.