IAPETUS
Iapetus
Iapetus, occasionally Japetus, is the third-largest natural satellite of Saturn, and eleventh-largest in the Solar System. Iapetus has a radius of about 42%, a density of about 32.5%, and a mass of about 2.5% of that of the Moon. Iapetus is best known for its dramatic 'two-tone' coloration, but discoveries by the Cassini mission in 2007 have revealed several other unusual physical characteristics, such as an equatorial ridge that runs about halfway around Iapetus.The above text is a snippet from Wikipedia: Iapetus (moon)
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