salty

Is dwarf planet Ceres potentially habitable?

by Passant Rabie
Updated: 
Originally Published: 

NASA/ESA/J. Parker (Southwest Research Institute), P. Thomas (Cornell University), L. McFadden (University of Maryland, College Park), and M. Mutchler and Z. Levay (STScI)

Ceres was discovered in 1801, and originally classified as an asteroid. But it is much larger than its Asteroid Belt companions, so its status is now 'dwarf planet.'

NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Ceres was the first dwarf planet to receive a visit from a spacecraft with NASA's Dawn mission, which arrived at the strange world in 2015.

Nathues et al., Nature Astronomy

Five years later, the Dawn spacecraft has sent back high-resolution images of Ceres revealing new, exciting details. The images suggest the dwarf planet is an ocean world, with a deep reservoir of brine, or salt-enriched water.

Dawn zoomed in on Occator crater, a massive impact crater on Ceres that stretches across 50 miles and is believed to have formed around 22 million years ago.

NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Previous observations of the Occator Crater had suggested that some sort of geological activity at the crater site had brought saltwater to the surface.

NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The latest observations suggest the liquid came from a deep reservoir of brine, or salt-enriched water. The brine reservoir is likely about 25 miles deep and hundreds of miles wide — a global, salty ocean that, possibly, could still be escaping to the surface.

NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI

Scientists believe the reservoir is linked to cryovolcanic eruptions, or related to a type of volcano that erupts volatiles such as water, ammonia or methane, instead of molten rock, and is considered a phenomenon of the outer Solar System.

C. A. Raymond et al, Nature 2020

The data suggest cryovolcanism began just 9 million years ago on the dwarf planet. It was likely still active up until a million years ago, the data show — and may even be active today.

NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The latest discovery hints Ceres may be habitable. Its salt-water ocean could be rich in organic material.

Scientists will continue to pour over the data sent over by the Dawn spacecraft until a new mission heads for this unexpected ocean world — one to specifically explore its potential for life.