Encyclopedia > Saturn > Satellites > Mimas
Mimas (Saturn I) was discovered by Herschel in 1789.
Mimas is the smallest spherical satellites. It is a "big ball of dirty ice", riddled with impact craters including a large one bordered by the "walls of Herschel." Its orbital period is 22 hours and 30 minutes.
Characteristics | Values |
---|---|
Semi-major axis in km | 185 540 |
Revolution period | 0.942 days |
Rotation period | 0.942 days |
Orbital velocity | 14 km/s |
Inclination on the equator of Saturn | 1.56 |
Eccentricity of the orbit | 0.019 |
Equatorial diameter (Earth=1) | 0.031 |
Equatorial diameter | 418 km |
Visual magnitude of the opposition | 12.9 |
Flattening | 0 |
Mass (Saturn=1) | 8/100 000 000 |
Density (Water=1) | 1.4 |
Escape velocity | 161 m/s |
Reflectivity (geometric albedo) | 0.5 |
The highest peak | 7000m |
Deepest pit | 2000m |
Temperature at the surface | -200C |
Atmosphere | no |
Composition | ice silicates |