Ceres contains water ice, a feature apparently revealed by massive landslides similar to those that occur on Earth, suggests a new study published in the journal Nature Geoscience.
Landslides are not unique to Earth: they also occur on other heavenly bodies, and that includes dwarf planet Ceres. New findings documenting the feature add to the bulk of evidence that suggests Ceres contains water ice. Using data obtained from the Dawn spacecraft of NASA, a team of researchers from the Georgia Institute of Technology spotted massive landslides occurring in three different forms on Ceres, thereby revealing the concealed ice.
“It’s just kind of fun that we see features on this small planet that remind us of those on the big planets, like Earth and Mars,” says lead author Britney Schmidt. “It seems more and more that Ceres is our innermost icy world.”
The first type of landslides (Type I) are characterised by a round shape, and big size and thickness. The scientists also describe their ends as bearing “thick toes”. Their location is mostly at high latitudes, where the majority of Ceres’ theorised ice is thought to be (at the poles).
Type II constitute the most common of the landslides observed on Ceres. They resemble the leftover-deposits of avalanches on our own planet. Thinner and longer than Type I, they were identified at mid-latitudes.
Fun fact: one of the Type IIs has been nicknamed ‘Bart’ from “The Simpsons”, because it reminded the researchers of the character’s very long head.
Finally, Type III are found at lower latitudes, and appear to originate from craters that were created from huge impacts that would have melted some of the ice.
Schmidt says Ceres has a shallow subsurface made up of both rock and ice. According to her, the greatest area covered by the landslides are at the poles, rather than at the equator, with ice influencing their characteristics—this would explain why the poles, having more ice, would also have big and thick landslides, while lower altitudes have fewer.
Studying the landslides is hoped to provide more information about the upper kilometres of Ceres, explains co-author Heather Chilton. The researchers have concluded that upper layers of Ceres might constitute from 10% to 50% ice by volume; they based their calculations on the shape and distribution of the landslides.
Ceres has been in the news several times before thanks to the data provided by Dawn spacecraft. Two years ago, two bright, mysterious patches were observed, that were thought to be evidence of ice or salt; for long, the two shiny spots were the object of much debate (some even mentioned aliens!) Another of the famous features of Ceres is the Ahuna Mons, its ‘pyramidal’ mountain. Read more here.