Object Analysis

Charon is the largest of the five known natural satellites of the dwarf planet Pluto. It has a mean radius of 606 km, making it more than half the size of Pluto itself. Because of this massive size relative to its primary, Charon and Pluto are often described as a double dwarf planet system, as their center of mass (barycenter) lies in the space between them.

The New Horizons mission in 2015 revealed Charon to be a world of unexpected geological complexity. It features a massive canyon system, the Serenity Chasma, which is four times longer than the Grand Canyon. Its northern pole is capped with a dark, reddish region nicknamed "Mordor Macula," likely composed of organic macromolecules called tholins filtered from Pluto’s atmosphere.

Unlike Pluto, which is covered in nitrogen and methane ices, Charon’s surface is dominated by less volatile water ice. This suggests that Charon lacks the internal heat or atmospheric pressure to maintain the shifting "glaciers" seen on Pluto, resulting in a frozen, rugged moon that preserves its ancient impact history.