Galileo, launched October 18, 1989, required almost six years to reach Jupiter after looping past Venus once and Earth twice. The Galileo spacecraft was designed to make a detailed study of Jupiter and its rings and moons over a period of years. On December 7, 1995, it released a probe to analyze the different layers of Jupiter’s atmosphere. Galileo recorded a multitude of measurements of the planet, its four largest moons, and its mammoth magnetic field. The mission was originally scheduled to continue until the end of 1997, but, since it continued to operate successfully, missions exploring Jupiter’s moons were added in 1997, 1999, and 2001. Galileo ended on September 21, 2003, when it passed into Jupiter’s shadow and disintegrated in the planet’s dense atmosphere.