Personally I feel that if we are alone, its an awesome responsibility for us to see Earth's biosphere expand to other planets, and we should start with Terraforming Mars right away.
If we can't actually spread humanity to other planets, I would still like it if we could launch some "simple" life-forms on some vessels to some other planets to acts as a "seed" to their evolution. If we succeed, we'll have created a whole other world of diversity.
This is based on the hope that such life could evolve the ability to enjoy life. If it's all just endless suffering of a thousand varieties, I won't forgive myself; but if at some point a form of life evolves that actually enjoys
life, it'll have been worth it.
And I don't consider Homo sapiens
the only species on Earth capable of enjoying life. Any sentient being with very basic emotional faculties will be happy from time to time in normal circumstances.
As for communication with another species, the size of space and time is such that it is very likely that sapient life occurs more than once, but the sheer scale of it all also implies that it is extremely unlikely that two sapient types of life would exist around the same time and the same place, close enough to ever know of each other.
If we can colonise Mars, we should do it. It would not guarantee that Earth-type life would survive any cosmic or planetary disaster, but it vastly improves the odds of it. The idea that we could in theory be in a situation where we would recover from the loss of an entire planet brings me great joy, and I don't think it's implausible that it could come to pass - though I would expect it to take centuries.
edited 10th Dec '11 4:41:32 PM by BestOf
Quod gratis asseritur, gratis negatur.