Tags: Planet.
Iapetus (/aɪˈæpɨtəs/; Greek: Ιαπετός) or occasionally Japetus /ˈdʒæpɨtəs/ is the third-largest natural satellite of Saturn eleventh-largest in the Solar System and the largest body in the Solar System known to not be in hydrostatic equilibrium. Iapetus is best known for its dramatic ‘two-tone’ coloration but discoveries by the Cassini mission in 2007 have revealed several other unusual features such as a massive equatorial ridge that runs three quarters of the way around Iapetus.
