The new image shows a color-coded topography of Serenity Chasma captured by the Long-Range Reconnaissance Imager (LORRI) on New Horizons. Measurements of the feature's shapes reveals that Charon's water-ice layer was once at least partially liquid before freezing solid.
NEWS: Night Falls on Pluto's Largest Moon Charon
Scientists have said that Charon may have housed a layer of liquid water, the same material that makes up Charon's surface. The decay of radioactive elements, combined with the internal heat produced by Charon's formation, could have caused the deeper water-ice to melt. As the moon cooled over time, the ocean would have frozen and expanded. Like with an overly full plastic cup of water left in the freezer, the surface was pushed outward, with tearing resulting in the detailed system of chasms, scientists said.
It's also thought that Pluto once hosted a liquid ocean, though the younger surface of the dwarf planet suggests that this ocean took longer to freeze than Charon's.
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