Like a lot of scientifically inclined technophillic folks, the space shuttle’s last flight makes me feel a little melancholy. I believe there are very good reasons to send people off world. If we are both lucky and conscientious then in the fullness of time humanity — or whatever inherits our history — will mediate the migration of the terrestrial biosphere beyond this pale blue homeworld. In doing so, we will ensure, or at least increase the probability, of life’s persistence into deep cosmological time and space. This goal, or something akin to it, is what has motivated a lot of people (myself included) to work on space exploration over the last half century. It is an enduring motivation, but to the public at large and to policymakers, I think it comes off as esoteric, cultish, or at least eccentric.