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.
|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|
|Mass (Saturn=1)||8/100 000 000|
|Escape velocity||161 m/s|
|Reflectivity (geometric albedo)||0.5|
|The highest peak||7000m|
|Temperature at the surface||-200C|