During its nearly eight-year mission from December 1995 to September 2003, Galileo transformed our view of the Jovian system. The stage for Galileo’s show was set more than 20 years ago. When the two Voyager spacecraft sped by Jupiter in 1979, they sent back data that made instant scientific celebrities of the giant planet’s four big moons. Io, Europa, Ganymede, and Callisto, known collectively as the Galilean satellites, had been tied to many key milestones in physics and astronomy since their discovery by Galileo in 1610. Among the milestones were Ole Roemer’s measurement of the speed of light, Pierre-Simon Laplace’s mathematical investigation of resonant orbits, the determination of longitude, and Albert Michelson’s development of the stellar interferometer. Voyager’s reconnaissance made the Galilean satellites targets for exploration on a par with the Moon, Mars, and Venus. Io’s volcanoes, Callisto’s cratered landscape, Ganymede’s icy tectonics, and enigmatic Europa’s smooth, fractured,...
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1 April 2004
April 01 2004
Special Issue: A Look at the Galilean Satellites After the Galileo Mission
From volcanic eruptions hotter than those typically found on Earth to ocean sandwiches with water trapped between ice layers, the Galileo mission revealed fascinating phenomena on Jupiter’s four largest moons.
Physics Today 57 (4), 77–83 (2004);