This is an image of the surface of Io,
looking down on a volcano and the lava plain surrounding it,
as well as the geyser Pele.
Click on image for full size
NASA
The surface of Io is completely covered with lava flows, as shown in this image. The red outline in the middle of the image is the remains of material ejected from the geyser Pele. White patches in the image are areas of frost.
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