That seems to be the conventional scientific wisdom. The mission to get to Mars is all over the news now. I totally get the appeal of the challenge; the adventure of it all. And, it’s something that could be done, even if not all of the technology exists yet, we should be able to develop it in the next few decades. Yes. I agree. We should definitely go to Mars. We need more justification than just that though; that it would be a cool thing to do. We need reason to spend that much time and money; something that will generate the political will to take on the task of getting us there. That reason I’ve heard expressed as “Our time on this planet is limited. Whether we destroy the planet ourselves or we get hit by an asteroid, it’s only a matter of time. If we want our species to survive, we have to become multi-planetary.” I’m not buying it. It doesn’t matter what we do, our species is not going to survive. We’ll live until we blow the planet up, or an asteroid scores a direct hit. Maybe we last until the earth’s core cools enough in about three and a half billion years to make the planet uninhabitable like Mars is already. It’s just a matter of time. We could become multi-planetary as a delaying tactic, so we can last longer than the planet earth, but we’ll still run out of time. As the sun runs out of fuel and becomes a red giant in about five billion years, it will expand, enveloping the current orbit of the earth. Not much chance of surviving that. If we become inter-stellar; moving to other planets around other stars in our galaxy, that’s only another delaying tactic. The fabric of time and space continues to expand. The distance between stars and galaxies increases. Our knowledge of the Universe is limited by the speed of light. We only know what we can detect. Eventually all the stars and galaxies will be so far apart the light from one will never reach another. We will be alone in the Universe again, with no way to tell if there are any other worlds still out there; nowhere else to migrate to, and if we do survive until then, no-one will ever know. We signed up for another night.