NASA's 2014 Rosetta Mission was full of firsts—the first craft to orbit a comet, the first craft to land on a comet, and more. Here, Exploratorium Senior Scientist Paul Doherty fills you in on the details of the mission—where the NASA spacecraft is going, where it's going to land, and how scientists expect to slow a speeding spacecraft the size of a minivan using the weight of four one-liter water bottles.