Of all the places to land on Mars, where in the world should the twin rovers in 2003 go? This question has been on the front burner of discussion with Mars scientists who have the arduous task of selecting a site where it is safe to land and yet is rich in rocks, layered terrain and other geologic features that will beckon a host of scientific inquiries and discoveries for the Mars Exploration Rover mission scheduled to launch in 2003. Mars scientists all agree on one thing: the search is on for landing sites where water was once present on the surface of Mars.