MESSENGER, Mercury
Orbiters tend go to out with more of a bang than rovers. Cassini’s plunge into Saturn’s atmosphere was thrilling, yes, but imagine the sound a craft would make hitting a rocky world’s surface at full speed. That’s what happened to NASA’s MESSENGER orbiter, the first spacecraft to ever orbit Mercury. It encircled the closest planet to the Sun for four years (three more than planned!), culminating in its greeting the world head-on. On April 30, 2015, MESSENGER transmitted an image of Jokai, a crater about as wide as the English Channel. It was the last image the trailblazing spacecraft would send; later that day, it crashed just north of the planet’s Shakespeare basin. It was pretty dramatic—the bard would’ve been proud.
