This is an image of Io.
Click on image for full size
Io was first discovered by Galileo in 1610, making it one of the Galilean Satellites
. Of the 60 moons it is the 5th closest to Jupiter. Io is the 4th largest moon of Jupiter, with a diameter about 2/3 the distance across the United States.
Io is named after one of Jupiter's many girlfriends, from Roman mythology. It is the only moon known to have active volcanos on the surface.
Because of all the lava, the environment of Io is pretty unfriendly to life as we know it on earth.
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