Charon's Mountains Reveal Moon Once Spun 10x Faster

• NASA's New Horizons flyby data suggests Charon was rotating more than 10 times faster in its early history than it is today.
• New research from UCLA, published in Nature Communications, uses computer modeling to link tectonic patterns in the Oz Terra region to this ancient rapid rotation.
• The study confirms a long-standing "despinning" hypothesis, providing a model for understanding the formation of icy moons across the outer solar system.

Scientific Findings

• UCLA researchers simulated early conditions on Charon, estimating an initial rotation period of 14.3 hours compared to the current 6.4 days (153.3 hours).
• The moon's initial ice shell thickness is estimated to have been between 30 and 36 kilometers (18-22 miles).
• Global contraction occurred alongside despinning, supporting a "cold start" evolutionary history for the moon.

Geologic Context

• Oz Terra in the northern hemisphere features complex, fractured mountainous terrain, contrasting sharply with the smoother southern Vulcan Planitia.
• The despinning process is believed to have predated any cryovolcanic activity, suggesting these tectonic features formed very early in Charon's history.

Significance

• Because Charon has remained relatively undisturbed by impact cratering or internal heating compared to other moons, it serves as a "testbed" for studying icy moon evolution.
• Insights gained here will aid in reconstructing the histories of moons orbiting Jupiter, Saturn, Uranus, and Neptune.