The last time Mars passed within 34,646,418 miles from Earth, give or take a few hundred yards, Neanderthals were gazing up at the skies. This time, we’re not just looking. We’re thinking about going there someday. This morning’s close encounter occurred as Mars was at its nearest point to the sun. NASA and the European Space Agency have taken advantage of this proximity by launching rovers due to land on the Red Planet by early 2004. But what about sending people?