The Magellan spacecraft, named after the sixteenth-century Portuguese explorer, was launched by NASA on May 4, 1989; it was the first scientific spacecraft to be launched from a space shuttle, the Atlantis. The spacecraft reached the planet on August 10, 1990. Magellan was equipped with a sophisticated Doppler radar mapping system, which astronomers used, along with altimetry and radiometry data, to measure and map the planet with unprecedented accuracy. Magellan ultimately made a three-dimensional map of 98 percent of the surface of Venus, and was able to measure features with a precision of 100 meters (330 feet).

After concluding its radar mapping, Magellan transmitted a constant radio signal. By measuring changes in the frequency of the signal as Magellan orbited, astronomers were able to use the spacecraft to make global maps of Venus’s gravity field. After four successful years of the scientific study of Venus, the Magellan mission ended on October 11,1994. Flight controllers flew the spacecraft into the atmosphere and onto the planet’s surface, the first time an operating planetary spacecraft had ever been intentionally crashed.