In a “clean room” in Building 150 of NASA’s Jet Propulsion Laboratory is something that looks very much like a flying saucer. It’s a capsule containing a huge, brawny Mars rover, a Hummer compared with the Mini Coopers that have previously rolled across the Red Planet.
This is the Mars Science Laboratory, the space agency’s next big mission to the most Earth-like planet in the solar system. But it’s been a magnet for controversy, and a reminder that the robotic exploration of other worlds is never a snap, especially when engineers decide to get ambitious.