For cosmic tire-kickers, NASA's Mars rovers were always special. Then, Curiosity came along: twice as long and five times heavier. The mission was like shot-putting a Mini Cooper 352 million miles, then perfectly hitting an entry window to the planet -- a zone measuring about 3 by 19 kilometers, a microscopic target after that long a distance.
You hit the thin atmosphere at 13,200 miles an hour -- 3-point-7 miles per second -- a real need to slow down, fast: enter friction and deployed heat shield, then 'chute, slowing from 900 miles an hour to 180 in just two minutes, then sky crane, to surface.
Cross your fingers, and hope a long list of mission-critical events, all closely timed and exactingly choreographed, happen precisely on cue. No pressure: We're just trying out a trunkful of new landing operations, is all -- Talk about a mission with lots of precisely-moving parts!