Cosmic Scale
Charon
Moon of Pluto · 5.9 billion km from the Sun
How big is Charon?
Charon is about 1,212 km across.
See Charon in 3D, at true scale
Charon is half the width of Pluto, so the two do not simply orbit one another: they both circle a point in empty space between them, always showing each other the same face. New Horizons revealed canyons far deeper than the Grand Canyon and a rust-coloured polar cap.
At a glance
| Diameter | 1,212 km |
|---|---|
| Mass | 1.59 × 10²¹ kg |
| Diameter compared with Earth | 0.095 × Earth |
| Orbits | Pluto, every 6.4 days |
| Surface | About −220 °C |
| Discovered | 1978 |
Good to know
- Its dark red north pole is nicknamed Mordor Macula; it is probably methane escaping from Pluto and freezing onto Charon.
- From Pluto's surface Charon would hang motionless in the sky, seven times wider than our full Moon.
- A canyon system runs 1,800 km along its equator, in places 9 km deep.