The space probe Cassini discovered the relatively dense atmosphere at Enceladus (Enceladus) — Saturn's moon.
The opening of "committed" Cassini magnetometer on the typical fluctuations and local deflection Saturn's magnetic field caused by its interaction with molecules of the atmosphere of Enceladus.
According to the measured frequencies of oscillation of the field, the atmosphere — nothing like ionized water vapor.
Enceladus has a diameter of 500 kilometers, and it is massive enough to hold the relatively dense atmosphere.
Because scientists have concluded that this atmosphere is a source of replenishment — volcanism, geysers, or gases emissions with or below the surface of the satellite.
If confirmed volcanic activity — Enceladus will join two other bodies in the solar system (besides Earth), which is found on the active volcanoes — is Jupiter's moon Io and Neptune's moon Triton.
Enceladus as curious as the planet with the most high-reflection among all the bodies in the solar system — its albedo is 90%. It is approximately seven times greater than the percentage of light that reflects the Earth's moon.
Ice volcanoes, regularly updating and supplying surface water ice on it, could explain this property Enceladus. The albedo of freshly fallen snow, by the way, is 95%.