Sunday, March 16, 2008

Human Outcomes Among the Stars

Do we have a human, biological future in interstellar space? If so, it surely must involve one of two things. Either we do develop a breakthrough technology for single-lifetime travel between the stars, or we take a lead from transhumanism by finding out just how far people can be altered to make potentially millennial journeys bearable.


Derek C. F. Pegritz said...

OR we do the smart thing and finally admit to ourselves as a species that biological Humans of ANY sort do not belong in space, period. In a mature, self-sustaining biosphere (either naturally-evolved or produced via terraforming), biological Humans can and do thrive. But take an average 1.0 Human and toss it into space: without all manner of extremely expensive devices to keep that Human alive, it will die in seconds. Let a Human float around in microgravity for too long and their immune and vascular systems crash; osteoporosis, furthermore, progressively destroys bone structure, too, beginning a few weeks after entering a micrograv environment.

Bioengineering to extend lifespan, correct for microgravity problems, and tailor Humans of any sort for an existence in interplanetary/interstellar space is ultimately futile for one simple reason: no matter how much engineering you do on an organic creature, it is still organic. Which means, it can only effectively exist in a biosphere or some sort. Organic beings of any sort do not last long outside of planetary environments or large, expensive protective habitats.

We've got to face it: organic Humanity will only make it to the stars in one form--as data carried there by inorganic machines that can easily survive the journey, i.e. in seedships. Organic Humans could no doubt be bioneered to better withstand interplanetary journeys, but no interstellar journey at any speed greater than .1c will ever be possible for even an extremely-long-lived, damnear immortal organic. The faster you go, the worse the blueshifted radiation that you're flying into. Thus, the need for heavier shielding...which means a much heavier, much slower ship. If you're organic and you want to visit Alpha Centauri, you'll need to take a few thousand years out of your life to get there in any reasonable amount of time.

Space belongs to the inorganic. Until wormhole production becomes possible, interstellar traffic will be entirely unsuitable for even the toughest, most long-lived organic. And even then, Humans will need machines to take one end of a wormhole pair to its destination while the other remains behind.

So, rather than waste time engineering Humans for space, we need to get busy developing Machine Intelligence...and then persuading it to help us spread throughout the Galaxy.

W.M. Bear said...

A foreseeable technology for human interstellar necessarily involves some sort of matter-antimatter reactor. The British Interplanetary Society did a study of exactly such a system of number of years ago and cam up with a design capable of achieving .1 c or one-tenth the speed of light. I'm guessing more highly sophisticated designs might be able to double or triple that but probably not much more. At that point, you start reaching the limits of what is physically possible. (I actually made this calculation once, and this is even assuming a perfectly efficient matter-antimatter reactor -- don't forget, you also have to slow down when approaching your destination.)

Turns out, though, this is actually fast enough to easily reach the nearest stars within a human lifetime, especially an extended one. One-third C makes Alpha Centauri a voyage of some dozen years (several more, considering the time to accelerate and decelerate). Not all that long compared even to some sea voyages of the early days of exploration of the Americas. (I am counting total time spent on a voyage, not the time to landfall.)

Therefore, I'm betting that we'll do it eventually. Right now, I'd be happy just to see a humanned planetary exploration program put in place. I believe humanity will stagnate if we willfully out of some ideological motive such as derek suggests confine ourselves to a single planet.

I also believe that the future of human evolution -- which will be mainly mental and cultural from now on and NOT biological -- lies in space exploration. Call me a romantic in this area. It's where I part company with a lot political liberals (of which I otherwise am one).

Anonymous said...

Humanity will find a way. It is in our nature to explore. The real breakthrough won't be biological but our manipulation and mastery of space/time. We'll eventually find a way to cross the void without taking any time at all ;)