Enceladus

Ownership: UCP
Mass: 0.65 x 10^20 kg
Radius: 256 x 247 x 245 km
Mean density: 1000 kg/m3
Visual geometric albedo: 1.0

Enceladus is a cold moon 500 kilometers in diameter, orbiting 238 020 km from Saturn. It is one of the most reflective objects in the Sol system and reflects almost 100 percent of the amount of light falling on it. This may be due to ice volcanoes or geysers that erupt material that falls back down on the surface, or even gases escaping from the interior of the moon.

These ice volcanoes on Enceladus have erupted material far out enough to create Saturn's E-ring. Saturn's rings, which are close to the orbit of Enceladus consist almost entirely of pure water ice, but some of the rings have been coloured by meteoric debris of millions of years. Enceladus has eluded this "miscoloring", which suggests that something is renewing the appearance of it (maybe the volcanoes or geysers are behind this?)

Enceladus orbits Saturn within its radiation belts, and is constantly being pelted by their high-energy particles. This bombardment of Enceladus causes material to be lost to the moon's surface.

Atmosphere

Enceladus has a small dynamic atmosphere made up of water ice. However, the gravity of Enceladus is too weak to hold on to it for a longer period of time.