Apollo 13 was the 3rd attempt to land humans on the Moon and the 1st to fail. Fifty-six hours into the mission, an explosion forced the crew to abort their Moon landing and take shelter in the Lunar Module. The crew ultimately returned to Earth safely.
As I was beginning my research for my two magazine articles on the Curiosity rover's upcoming mission to Mars, I needed to figure out for myself how exactly this gigantic, ungainly machine fit in to the context of past Martian missions.
It's still three weeks until Curiosity's launch date, but the spacecraft has already been placed on top of its rocket. The Kennedy Space Center's Curiosity photo album now has lots of pictures of the spacecraft being enclosed inside the payload fairing (the rocket's "nose cone") and hoisted to the top of the Atlas V.