This picture shows many photos of Europa and its surface taken during the Galileo mission. There are many interesting surface features on this moon.
Click on image for full size
NASA
Surface of Europa
Many exciting discoveries were made about Europa during the
Galileo mission. The surface of Europa is unusual, even for an icy moon. It appears that the surface is pretty new, rather than being ancient. Instead of craters, there appear to be strange cracks that reach for many kilometers over the surface of the moon. Closeup images of the surface suggest that there might be an
ocean under the icy surface.
The surface of Europa also shows a form of volcanism found on Earth as well as on icy moons called
icy-volcanism. Other features include changes in the icy crust common to places where volcanism is found. The surface also shows evidence of
new molecules that form because of
radiation in the environment!
All this evidence for geologic activity points to a heat source in the interior of Europa.
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