It’s no secret that the greatest obstacle to colonizing the stars is distance. Living in a time when the Earth can be circled in 24 hours, the prospect of the “light year” is unthinkable to us; that unit means that even at the speed of light, the fastest speed allowed by the laws of physics, our “instant” wireless communications themselves would take a year to get from point A to point B. That means that at a mere one light year from Earth, the time from sending “Hello, how are you?” to receiving “Fine thanks, and you?” is two years.
The nearest star to Earth is 4.2 light-years away. That’s eight and a half years between “How are you?” and “Fine.”
It’s interesting to consider what we see as the biggest obstacle to crossing that distance. Once upon a time, it was technology; how would we feed human colonists through the dozens or hundreds of years it might take to cross interstellar space at sublight velocities? How would they breathe, or generate power? But as modern science advances at an ever-accelerating pace, we have some pretty good ideas about how to answer those questions. It could be argued that with sufficient funding, a self-sustaining colony ship could be constructed within our lifetimes.
No, the seemingly insurmountable obstacle to space colonization is no longer technical–it’s social.
Our biggest anxiety about sending astronauts to Mars is that, if something should go wrong, they’d be utterly out of reach of Earthly help. This was not an overpowering concern when we sent astronauts to the moon decades ago, even though they were in basically the same situation; they were days away from Earth, but in an era when space shuttle flights were far from routine, those in the Moon’s orbit were just as effectively separated from Earth as today’s astronauts would be on Mars–a journey that takes months or years, one way.
No rescue missions would get to our Mars explorers before they ran out of air. Those bound for Proxima Centauri would have even dinner hope of rescue–once their expedition left the range of easy radio contact, we would not even hear of its success or failure for years.
Now, let’s crank this up a notch: Kepler 22b, the possible Earth analogue, is a staggering 600 light years away.
That’s 1,200 years between “How are you?” and “Fine.” That is dozens of human generations spent aboard a starship traveling at sublight velocities.
The payoff would be amazing. A second Earth. An entire second human history. A continuation of our species, should catastrophe happen here. A second base from which mankind could colonize even more stars.
But to we as a society have the collective will to do it? Could we invest the trillions of dollars necessary to create such a journeyship, for a payoff we would not see for centuries? Could we send dozens, hundreds, or thousands of personnel into unknown territory beyond reach of our help? Them, and their great-grandchildren?
Paul Gilster writes for the Tau Zero Foundation, a society dedicated to answering just these questions. He–like many scientists and science fiction authors–believes that travel to the stars, as soon as possible, is the best way for humanity to ensure our continued survival. And through the Tau Zero Foundation, he aims to nurture not just the physical underpinnings–the funding and the technological advances for such a mission–but also the psychological foundation needed for humanity to again undertake risky, long-term endeavors.
Endeavors which would not have been alien to our forefathers, who spent months crossing the Atlantic Ocean in wooden boats, without even the benefit of electricity; endeavors which have now become alien to us, shaped by the comfort, safety, and instant gratification of the information age.
Will our modern safety standards and needs for short-term payoff be our downfall? Weigh in in the comments.