Pluto's giant "bite mark" recently discovered on the dwarf planet's surface has NASA officials wondering, "What's eating Pluto?"
The space agency released photos last week of the area, discovered by the recent NASA New Horizons mission, that appear to show a huge bite mark. Space officials say, according to Thursday NASA statement, that a process called sublimation seems to be at play.
Sublimation is created by the transition of a substance from a solid to a gas, and scientists believe that Pluto's methane ice surface may be transitioning into the atmosphere, exposing water-ice beneath, according to the NASA statement.
The "bite mark" photos were taken in the Piri Planitia area of Pluto and captured by the New Horizons spacecraft from about 21,100 miles away on July 14, 2015.
"Water ice, for example, at sea level pressures on Earth will melt into a liquid and then boil into a vapor
(or gas) when heated," Discovery News reported. "On Pluto, because it's so cold and the pressures are a near vacuum, liquid water is not possible and heated water ice will sublimate directly from a solid into a gas."
"And it appears that's what's happening with the methane ice in Piri Planitia; it's sublimating into Pluto's thin atmosphere, likely contributing to the dwarf planet's atmospheric cycles of surface ices and exposing water ice-rich layers below."
NASA's New Horizons spacecraft left Earth in 2006 and reached Pluto last year. It conducted a six-month-long reconnaissance flyby study of the dwarf planet and its moons, making its closest approach on July 14, 2015.
The spacecraft is expected to head toward the Kuiper Belt to examine another one of the ancient, icy mini-worlds at least a billion miles past Neptune's orbit, according to NASA.
Before New Horizon left Pluto, it also took shots of its five moons — Charon, Styx, Nix,
Kerberos, and Hydra, according to Space.com.