Surprising data from NASA’s Dawn spacecraft suggests that the dwarf planet Ceres has native carbon compounds that were not delivered by collisions with other objects. These compounds were discovered in the region on Ceres that contains the Ernutet crater (pictured above).
While it is possible for organic molecules to form through chemical processes that have nothing to do with life, Ceres is a dwarf planet that is large enough to host substantial reservoirs of water under its surface and may still have some internal heat from its formation billions of years ago. The same underground activity that makes Ceres’ active ice water volcano possible may also heat some of this water periodically. This makes it one of several “rocky” worlds throughout the solar system that may be capable of hosting rudimentary life.
There may also be carbon-rich regions on Ceres that were not surveyed by Dawn’s science team. The study team led by Maria Cristina De Sanctis of the Institute for Space Astrophysics and Space Planetology in Rome focused on latitudes on Ceres that lay between 60 degrees north and 60 degrees south.
“We cannot exclude that there are other locations rich in organics not sampled by the survey, or below the detection limit,” De Sanctis told Space.com.
The chemical signatures detected by Dawn resembled tar-like substances such as kerite and asphaltite. These are substances that would likely have been destroyed by the heat produced by collisions with asteroids and comets. However, they could have formed in the presence of underground reservoirs of hot water. How the tar would have made it to the surface after forming underground remains a mystery to the research team. De Sanctis mentioned that the team is still analyzing high-resolution data that Dawn gathered on the geological and morphological settings found in the Ernutet region.
Until the analysis is complete, scientists are cautious about giving any definitive answers regarding this mystery. However, astrobiologists are increasingly intrigued by the organic compounds found on Ceres. “In some ways, it is very similar to Europa and Enceladus,” De Sanctis said, referring to moons orbiting Jupiter and Saturn.
The team’s study on Ceres’ organics was published in the journal Science on February 16, 2017, adding to the impressive discoveries made possible by NASA’s Dawn probe.