Dwarf Planet Ceres Has A Lot More Carbon Than Previously Imagined

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Earlier this year, the Inquisitr reported that Ceres, the only dwarf planet in the inner solar system, holds vast amounts of organic material on its surface. The revelation came after scientists from Brown University in Rhode Island examined fresh data collected by NASA’s now-retired Dawn mission — and uncovered that Ceres hosts a lot more organic matter than previously believed.

Their conclusion is now corroborated by a new study based on Dawn data, published yesterday in the journal Nature Astronomy. This recent research revealed that the surface of Ceres is chock-full of carbon, present in large concentrations that exceed those found within carbonaceous chondrite meteorites — ancient meteorites which formed in the early days of the solar system, and later came together to create primitive asteroids.

According to Phys.org, Ceres’ surface may hold up to 20 percent carbon — or five times as much as these carbon-rich meteorites, which are often discovered on Earth and are known to contain both water and organic compounds. In fact, the carbon found on Ceres’ surface is actually locked away in compounds called phyllosilicates and carbonates, which represent “products of rock–fluid interactions,” the authors wrote in their paper.

“Ceres is like a chemical factory,” said study lead author Simone Marchi, a scientist at Southwest Research Institute (SwRI) in Texas.

“Among inner solar system bodies, Ceres’ has a unique mineralogy, which appears to contain up to 20 percent carbon by mass in its near surface. Our analysis shows that carbon-rich compounds are intimately mixed with products of rock-water interactions, such as clays.”

Image of the dwarf planet Ceres, taken by NASA's Dawn spacecraft on May 7, 2015, from a distance of 8,400 miles.
Image of the dwarf planet Ceres, taken by NASA's Dawn spacecraft on May 7, 2015, from a distance of 8,400 miles. Featured image credit: NASAWikimedia Commons/Resized

The largest resident of the Asteroid Belt, Ceres has been studied by the Dawn spacecraft for the past three years. The NASA space probe closely imaged the dwarf planet right up until it ran out of fuel at the end of October, producing unparalleled views of the 600-mile-wide rocky body. In late June, Dawn captured the closest-ever photo of Ceres, taken from a distance of 21 miles from the dwarf planet’s surface, as previously reported by the Inquisitr.

This latest study focuses on data recorded by two instruments on board the Dawn spacecraft — the Visible and Infrared (VIR) Mapping Spectrometer and the Gamma Ray and Neutron Detector (GRaND) — which picked up a discrepancy between the reflectiveness of Ceres’ surface and element distribution, notes Chemistry World.

The VIR findings revealed that Ceres has a low albedo — the ratio of reflected light — which pointed to the presence of a darkening agent, initially assumed to be an iron oxide called magnetite. However, since elemental data detected by GRaND were not consistent with large amounts of iron, the scientists concluded that the darkening agent on Ceres’ surface was carbon.

In addition, the SwRI team uncovered that 50 to 60 percent of the dwarf planet’s upper crust is actually very similar in composition to carbonaceous chondrite meteorites. This suggests that Ceres was heavily pummeled by carbon-rich asteroids in its distant past.

“Our results imply that either Ceres’ accreted ultra-carbon-rich materials or that carbon was concentrated in its crust,” said Marchi.

“Both potential scenarios are important, because Ceres’ mineralogical composition indicates a global-scale event of rock-water alteration, which could provide conditions favorable to organic chemistry.”

Last but not least, the scientists discovered organic compounds near the Ernutet Crater, a 31-mile-wide impact crater located in the dwarf planet’s northern hemisphere. This gives “further support to the widespread presence of organics in Ceres’ shallow subsurface,” SwRI officials said in a statement.