>and the sun going supernova will cleanup after us.
I've got terrible news! Our modest little sun isn't massive enough to end up as a nova. I think a star has to be about 10 or more solar masses to blow up, otherwise it just swells and then shrinks into a white dwarf. The good news is though that a billion years of the fully swollen sun baking the Earth will probably blast away or decompose all of the printers, plastic shopping bags and National Geographic magazines that are buried in landfill all over the planet. Oh! Even better news. I just read that the Earth might actually finish up inside the swollen sun. That will certainly solve the garbage problem. Greg
