Named in honor of the sixteenth-century Portuguese explorer Ferdinand Magellan, the Magellan spacecraft was a robotic space probe launched by NASA, via the Space Shuttle in 1989. Magellan was the first interplanetary mission to be launched from the Space Shuttle and it focused on mapping the surface of Venus and its planetary gravitational field. The mission was a success. The spacecraft mapped over 98 percent of the surface of Venus and, in so doing, unmasked its cloud-obscured surface for the first time. So comprehensive were Magellan’s results that they revealed more about Venus in four short years than had been achieved in centuries of ground-based observation.