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We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.
This picture shows images of the Galilean Satellites taken by the Galileo spacecraft, as well as details from the surfaces of these moons.
Click on image for full size
NASA

Galilean Satellites

The Galilean satellites are the 4 big moons of Jupiter, Io, Europa, Ganymede, and Callisto. These moons are called Galilean because they were discovered by Galileo Galilei in 1610.

In this picture, Io, and Ioís surface, are shown on the left-most end, then Europa, and its surface, then Ganymede, then Callisto. Of Jupiterís 60 moons, these four are the biggest.
Last modified September 18, 2003 by Roberta Johnson.

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