Mimas Information Page

Less than 123 miles (198 kilometers) in mean radius, crater-covered Mimas is the smallest and innermost of Saturn's major moons. It is not quite big enough to hold a round shape, so it is somewhat ovoid with dimensions of 207 x 197 x 191 km. Its low density suggests that it consists almost entirely of water ice, which is the only substance ever detected on Mimas. At a mean distance just over 186,000 km from Saturn, Mimas takes only 22 hours and 36 minutes to complete an orbit. Its most distinguishing feature is a giant impact crater – named Herschel after the moon's discoverer – which stretches a third of the way across the face of the moon,

urn:nasa:pds:context:target:satellite.saturn.mimas

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