Jupiter and moons. Composite image of the planet Jupiter with its four Galilean moons, superimposed on a starfield. Anticlockwise, from lower left, th

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Jupiter and moons. Composite image of the planet Jupiter with its four Galilean moons, superimposed on a starfield. Anticlockwise, from lower left, the moons are Europa, Callisto, Ganymede, and Io (appearing closest to Jupiter). These moons are the largest of at least 16 natural satellites of Jupiter. They are so big that if they orbited the Sun they would be considered planets in their own right: Ganymede is larger than Mercury. They were discovered by the Italian astronomer Galileo in 1610 using one of the first telescopes. Jupiter is mostly made of hydrogen and helium gas, but its moons mostly consist of ice and rock.

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Size: 5112px × 4180px
Photo credit: © Science Photo Library / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: astronomy, callisto, cosmology, europa, galilean, ganymede, io, jupiter, moons, planet, planetary, science