The tiny and irregular shaped Epimetheus orbits Saturn with a similar moon called Janus, both of which may have formed when a larger body was broken up during a collision earlier in its history. Because the density of Epimetheus is less than that of water, it may be porous, perhaps just a pile of rubble held weakly together by gravity.
Published by Richard Leis
Richard Leis (he/him) writes poetry and fiction. He lives in Tucson, Arizona where he teaches workshops at The Writers Studio and works for HiRISE, a team at the University of Arizona with a camera in orbit around Mars. View all posts by Richard Leis