Mimas

The conspicuous crater on the surface of Saturn's moon Mimas is seen in
this image taken by Voyager. The massive crater, whose proportionate size
(approximately 100 kilometers or 60 miles) is about one-quarter of the
satellite's diameter (390 kilometers or 235 miles), is without precedent
among the explored objects of the solar system. The impact that formed the
crater was probably almost large enough to shatter Mimas into two or more
fragments.

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