NASA’s Dawn mission has found regions of the dwarf planet Ceres that are constantly shadowed. This indicates that Ceres has the potential for holding water ice below the surface. These crater areas could have trapped water ice for a billion years, which suggests that ice deposits could still be there now.
Norbert Schorghofer, an investigator from the University of Hawaii, said that there are good conditions for water on Ceres. Apparently, the planet has enough weight to hold water molecules.Also, permanently shadowed regions at the poles are very cold, colder than the Moon or Mercury.
These regions do not have direct sunlight. They are usually located in craters at the poles. These regions only receive indirect sunlight, but if temperatures stay below -240 degrees Fahrenheit, the area in shadow acts as a cold trap. That’s an ideal place for water ice to accumulate and remain. Cold traps were thought to exist on the surface of Ceres, but could not be identified so far.
A latest generation computer model has determined which areas of the dwarf planet receive direct sunlight, how much radiation reaches its surface and how conditions change over the year on Ceres. Experts found many permanently shadowed regions within the northern hemisphere.
The largest such crater is a 10-mile wide one, located 40 miles from the north pole of the planet. Researchers expect that a greater reservoir of water ice may be found since conditions on Ceres might encourage icy deposits.
On the total, Ceres has 695 sq miles of shadowed surface.This is less than one percent of the total area of the dwarf planet’s northern region. On Ceres, cold traps are easier to find than on the Moon or Mercury, since these permanently shadowed regions do not get cold enough to store water ice on their surfaces.
Computer models have found that one of every 1,000 molecules of water on Ceres ends up in cold traps. At that rate, Ceres could host water ice deposits in the next 1,000 years.
However, conditions fluctuate on Ceres, and therefore we can’t know for sure if water exists beneath the surface. Further exploration and modeling need to happen before scientists reach a conclusion about water on the distant dwarf planet Ceres which apparently has the potential for water ice.
Image Source – Wikipedia