There's an old joke, described more fully at <a href="http://www.snopes.com/humor/jokes/moonshot.asp" rel="nofollow">http://www.snopes.com/humor/jokes/moonshot.asp</a> , that appears to have started with Johnny Carson in 1969. The short version is that a Native American recorded a message to be taken into space - "Watch out for these guys [US astronauts]; they've come to steal your land."<p>This link did not address a couple of important issues:<p>1) What resources are worth the expense? While there are ideas about platinum from asteroids or 3He from the Moon's crust, resource extraction from another planet is tremendously more expensive.<p>2) "..., it's probably best we ditch this planet anyways, along with everything on it." ... And what of the 7+ billion people? Leave them to die?