This is an image of Antarctic ice flowing.
Click on image for full size
USGS
Ice can flow inside an icy satellite
The figure to the left is an illustration of the flow of ice in the Antarctic region of the Earth. Ice flows readily, albeit slowly. Terrestrial glaciers are ample evidence of the fact that ice can move. Glaciers flow with a speed of about 2 inches per year. Thus the ice of a moon can readily flow inside a moon in response to being heated from within.
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