Solar System Chatter

Update to the Pluto Wiki

NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
From New Horizons data, scientists have drawn many new conclusions this month about the most famous dwarf planet. A team at Purdue University believes that an ammonia-water slurry underneath an icy layer is the cause for the planet’s surprising geological movements. The ammonia gives it a lower freezing point, leading to convection that could be causing volcanic activity. Meanwhile, the SETI Institute studied pictures of Pluto’s moons as New Horizons approached, and found that the smaller moons—Styx, Nix, Kerberos, and Hydra—are “spinning wildly.” Most moons, like our own, orbit in synchronous rotation, meaning one side stays facing the planet—a movement caused by the slow tidal pull from the larger planet. Instead, Nix is tilted and spinning backwards, and Hydra is spinning rapidly—89 times in each orbit. Scientists think the large moon Charon might be pulling on them, but even that’s not enough to explain the “pandemonium.” Finally, NASA just published a view of a full day on Pluto, at right.

Heather Goss is the Departments Editor at Air & Space.

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