NASA Wants Spacecraft For Mars Return Trip

coondoggie writes "If we ever do get to Mars, getting home might prove to be as difficult. NASA today selected three companies — Alliant Techsystems, Lockheed Martin and Northrop Grumman — to being the task of defining the spacecraft that will leave Mars, presumably at first loaded with red planet rock samples, then later possibly humans — for a safe trip back to Earth. The engineering challenges those three companies face are immense."