Galilean moon

Category:Jupiter\n\n\n\n\n\n The Galilean moons are the four moons of Jupiter discovered by Galileo Galilei. By far the largest of the many moons of Jupiter, they are visible even in a low-power telescope. They were first observed by Galileo on January 7, 1610. Galileo observed the moons' motion over several days and realized that they were in orbit around Jupiter. This discovery supported the heliocentric theory of Copernicus and showed that not everything revolves around the Earth. In order from closest to Jupiter to farthest away, they are: {| border="1" cellspacing="0" cellpadding="2"\n|- style="background:#efefef;"\n! Name\n! Diameter (km)\n! Mass (kg)\n! Mean orbital
radius (km)\n! Orbital period\n|-\n| Io\n| 3643\n| 8.93×10²²\n| 421,800\n| 1.77 days\n|-\n| Europa\n| 3122\n| 4.8×10²²\n| 671,100\n| 3.55 days\n|-\n| Ganymede\n| 5262\n| 1.48×10²³\n| 1,070,400\n| 7.16 days\n|-\n| Callisto\n| 4821\n| 1.08×10²³\n| 1,882,700\n| 16.69 days\n|}

• the volcanic Io\n*oceanic Europa\n*oceanic Ganymede\n*oceanic Callisto

See also: Jupiter's natural satellites