7 Remarkable Lessons from Messenger's Mission to Mercury

Through most of its life, NASA's scrappy Messenger probe was something of a unsung hero. The first spacecraft ever to orbit Mercury didn't have the you-are-there appeal of a Mars rover, the daredevil appeal of landing on a comet, or the romance of visiting a beautiful ringed planet. But with today's death--the result of a long-anticipated crash into the planet it studied--we can clearly see what an incredibly successful explorer Messenger was. Mercury has long been a solar-system enigma.