WASHINGTON, March 14 (UPI) -- While reviewing Pluto images captured by the New Horizons probe last summer, scientists noticed what looks like a giant "bite mark" on the surface of the dwarf planet.
Researchers believe the missing chunk of planetary flesh was lost via sublimation, a phase change from solid to gas. As a portion of Pluto's methane ice-rich surface vaporized, a patch of water ice was revealed below.