i don't care about colonizing mars beyond it being the closest planet to do so. The earth isn't going to be habitable sometime in the next billion years as the

i don't care about colonizing mars beyond it being the closest planet to do so. The earth isn't going to be habitable sometime in the next billion years as the sun gets hotter and then turns into a red giant. We (or life's other descendents) have to go somewhere. (the earth itself might also become less habitable all by itself over time, but i don't know enough about that)