Dwarf planet Ceres is ‘ocean world’ with salty water deep underground

Ceres, the largest object in the asteroid belt between Mars and Jupiter, is an “ocean world” with a large reservoir of salty water under its frigid surface, scientists said in findings that raise interest in this dwarf planet as a possible outpost for life.

Research published on Monday based on data obtained by NASA’s Dawn spacecraft, which flew as close as 22 miles (35 km) from the surface in 2018, provides a new understanding of Ceres, including evidence indicating it remains geologically active with cryovolcanism – volcanoes oozing icy material.

The findings confirm the presence of a subsurface reservoir of brine – salt-enriched water – remnants of a vast subsurface ocean that has been gradually freezing.

“There is major interest at this stage,” said planetary scientist Julie Castillo of NASA’s Jet Propulsion Laboratory, “in quantifying the habitability potential of the deep brine reservoir, especially considering it is cold and getting quite rich in salts.”