On June 10, 2003, a little rover named Spirit blasted off on a rocket headed for Mars. A month later, a twin rover named Opportunity soared through the solar system with the same mission: to find out if Mars ever had water that could have supported life. They were expected to last no more than three months on the frigid, harsh planet. Instead, they explored the red planet for years. Packed with full-color photos, this 80-page book is a thrilling addition to the acclaimed Scientists in the Field series, told through the eyes—and heart—of Steven Squyres, the lead scientist on the mission. This suspenseful page-turner captures the hair-raising human emotions felt during the adventures with two tough rovers.