Ice Volcanoes To Unravel Mystery Of Missing Large Craters On Dwarf Planet Ceres

Researchers discovered that the dwarf planet Ceres seems to lack any giant impact craters, although it has craters of small sizes. They used the data from NASA's Dawn mission for the search. The study indicates that certain geological forces on and within Ceres, probably cryovolcanoes or also known as ice volcanoes or the viscous relaxation of surface ice, could solve the dwarf's planet internal evolution.

The findings of the study were printed in the journal Nature communications. The study was led by Simone Marchi from the Southwest Research Institute and other colleagues, according to Los Angeles Times.

Dwarf planet Ceres has many small, young craters, but no big ones. Why?@NASA_Dawn examines: https://t.co/bUDmlxxoBHhttps://t.co/xd937Bysfg

— NASA (@NASA) July 26, 2016

Marchi along with the other scientists concluded that a weighty population of large craters on Ceres has been obliterated beyond recognition over geological time scales, which is likely the result of Ceres' peculiar composition and internal evolution.

Researchers foresaw the number of large craters of the dwarf planet since it was formed. These included 10 to 15 craters larger than 250 miles (400 kilometers) in diameter and at least 40 craters larger than 60 miles (100 kilometers) wide. On the other hand, with the data from the NASA's Dawn mission, there are only 16 craters larger than 60 miles and none larger than 175 miles (280 kilometers) across, according to NASA.

So, what causes the disappearance of the large craters? The researchers have theories regarding the case of the missing large craters. Probably the layer of subsurface liquids, which is salty and icy, is possibly flowing and thick. This substance let the craters become smooth over time and form a new surface, according to Tech Times.

Another reason could be linked to the interior structure of Ceres. The upper layers of Ceres comprise of ice. The topography could smooth out because ice is less dense than rock. The analysis of the center of Ceres' Occator Crater indicates that the salts found there could be remnants of a frozen ocean under the surface. The liquid water could have been present in Ceres' interior, according to NASA.

Marchi explained that whatever the process or processes were, this eradication of large craters must have happened over several hundred millions of years.