Known Space -- Sol -- Pluto -- | Charon |
Charon is unusual in that it is the largest moon with respect to its primary planet in the Solar System (a distinction once held by Earth's Moon). Some prefer to think of Pluto/Charon as a double planet rather than a planet and a moon.
Pluto and Charon are also unique in that not only does Charon rotate synchronously but Pluto does, too: they both keep the same face toward one another. (This makes the phases of Charon as seen from Pluto very interesting.)
It has been proposed that Charon was formed by a giant impact similar to the one that formed Earth's Moon. It has also been proposed that both Pluto and Charon are really Kuniper Belt objects rather than true planets.
Orbital Distance: 19,600 km (circular orbit) Eccentricity: 0.000 Local Year: 6.387 days (6d 9h 17m 16.8s) Orbital Velocity: 0.223 km/s Inclination: 98.800° Local Day: 6.387 days (6d 9h 17m 16.8s) Axial Tilt: n/a Diameter: 1,172 km Composition: Ice Density: 2.25 g/cm3 Mass: 1.90 x 1018 tonnes (0.0003 earths) Gravity: 0.04 G Escape Velocity: 0.658 km/s Area: 4.3 million km2 Surface Material: N2 ice, H2O ice, CO ice Atmosphere: None Pressure: None Albedo: 0.50 Temperature: ???°C |