Magellan, Galileo, and Ulysses

More recent U.S. planetary probes have been increasingly ambitious. Magellan was launched in May 1989 and ultimately placed into orbit around Venus. Using high-resolution radar imaging, Magellan produced images of more than 90 percent of the planet, yielding more information about Venus than all other planetary missions combined.
The spacecraft made a dramatic conclusion to its four-year mission when it was commanded to plunge into the planet’s dense atmosphere on October 11, 1994, in order to gain data on the planet’s atmosphere and on the performance of the spacecraft as it descended.
On October 18, 1989, Galileo was launched on a journey to Jupiter and transmitted data on Venus, the earth’s moon, and asteroids before reaching Jupiter on July 13, 1995, and dropping an atmospheric probe, which gathered data on Jupiter’s atmosphere. After an extended analysis of the giant planet, Galileo began a mission to study Jupiter’s moons, beginning with Europa. The so-called Galilean moons were discovered by the mission’s namesake, Galileo Galilei in 1610. The Ulysses probe was delivered into orbit by the shuttle Discovery on October 6, 1990. A joint project of NASA and the European Space Agency (ESA), Ulysses gathers solar data and studies interstellar space as well as the outer regions of our own solar system. Much of the spacecraft’s instrumentation is designed to study x-rays and gamma rays of solar and cosmic origin.