Ceres provides the first detection of the building blocks of life in the asteroid belt

NASA’s Dawn spacecraft has searched around Ceres since it was first launched into orbit in March 2015. During that time, the mission sent back a vapor of images of the minor planet, and with a level of resolution that was previously impossible. . For this reason, many interesting revelations have been made about Ceres’ composition and surface features (such as its many “bright spots”).

In what is sure to be the most startling discovery to date, the Dawn spacecraft has revealed that Ceres may actually possess the ingredients for life. Using data from the Dawn spacecraft Visible and infrared mapping spectrometer (VIMS), an international team of scientists has confirmed the existence of organic molecules on Ceres – a discovery that may indicate that it has favorable conditions for life.

These results – which were detailed in a study titled Aliphatic organic matter located on the surface of Ceres– published in the February 17, 2017 issue of Science. For the purposes of their study, the international team of researchers – led by Maria Cristina de Sanctis from the National Institute of Astrophysics in Rome, Italy, showed how data from the Dawn sensor indicated the presence of aliphatic compounds on the surface.

Enhanced color composite image from Dawn’s Visible and Infrared Mapping Spectrometer, showing the area around Ernutet crater on Ceres. Credit: NASA/JPL-Caltech/UCLA/ASI/INAF

Aliphatics are a type of organic compound where carbon atoms form open chains that are usually bonded with oxygen, nitrogen, sulfur, and chlorine. The least complex aliphatic is methane, which has been detected in many places in the solar system, including the Martian atmosphere and in liquid and gaseous form on Saturn’s moon Titan.

From their study, Dr. by Sanctis and his colleagues determined that the spectral data obtained by the VIMS instrument corresponded to the presence of these hydrocarbons in a region outside the Ernutet crater. This crater, located in the northern hemisphere of Ceres, is about 52 km (32 mi) in diameter. The aliphatic compounds that were detected were located in an area of ​​about 1000 square kilometers around it.

The team ruled out the possibility that these organic molecules were deposited from an external source – such as a comet or a carbonaceous chondrite asteroid. Although both have been shown to contain organic molecules inside in the past, the greatest concentrations on Ceres were discontinuously distributed on the southwestern floor and the rim of the Ernutet crater and on a crater older and very degraded.

In addition, other organic-rich areas have been identified and are scattered to the northwest of the crater. As Dr. Maria Cristina De Sanctis told Universe Today via email:

“The composition we see on Ceres is similar to some meteorites containing organic compounds and so we looked for this material. We considered both endogenous and exogenous origin, but the latter seems less likely for several reasons, including the greater abundance observed on Ceres compared to meteorites.

Data from the Dawn spacecraft, showing the absorption band of organics (warmer colors indicate higher concentrations). Credit: NASA/JPL-Caltech/UCLA/ASI/INAF/MPS/DLR/IDA

Instead, they considered the possibility that their organic molecules were of endogenous origin. In the past, studies have shown evidence of hydrothermal activity on Ceres, which included signs of surface turnover and fluid mobility. Combined with other investigations that have detected hydrated minerals containing ammonia, water ice, carbonates, and salts, all of this indicates that Ceres has an environment that may support prebiotic chemistry.

“The overall composition of Ceres may support pre-biotic chemistry,” De Sanctis said. “Ceres has water ice and minerals (carbonates and phyllosilicates) derived from the ubiquitous aqueous weathering of rocks. It also contains materials that we think form in hydrothermal environments. All of this information indicates that the condition n is not the inn of biotic molecules.

These findings are certainly important in helping to determine whether life could exist on Ceres – in a similar way to Europa and Enceladus, locked under its icy mantle. But given that Ceres is believed to have originated 4.5 billion years ago (when the solar system was still forming), this study is also significant in that it may shed light on the origin, evolution and distribution of organic life in our solar system.

Other members of the research team include researchers from the Department of Earth planetary and space sciences at the University of California, the Department of Earth and Planetary Sciences at the University of Tennessee, the Department of Earth, Environmental and Planetary Sciences at Brown University, Southwest Research Institute (SwRI), NASA Goddard Space Flight Center and NASA Jet Propulsion Laboratory.

Further reading: ScienceMag, SwRI

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