Fans on Crater Rims

Gas under pressure will choose an easy escape route. In this image, the terrain is covered with a seasonal layer of dry ice.

The weak spots, for gas sublimating from the bottom of the seasonal ice layer to escape, appear to be around craters, where the surface was broken and pulverized by an impact. Fans of surface material deposited on top of the seasonal ice layer show where the escape vents are .

This target was identified by the citizen scientists at Planetfour: Terrains .

Written by: Candy Hansen (audio: Tre Gibbs)    (14 December 2016)

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Image: NASA/JPL/University of Arizona