Saturday, June 16, 2018

Organics on Ceres may be more abundant than originally thought

A new study concluded that organic material on Ceres could be greater in concentration than previously thought. This is important information for scientists to consider as they evaluate data from two sample return missions over the next few years.

The Japanese spacecraft Hayabusa2 is scheduled for orbital insertion around asteroid Ryugu in July, survey for a year and a half, land at least once, and return to Earth in December 2020.

NASA’s OSIRIS-REx spacecraft is scheduled for orbital insertion around the asteroid Bennu in August with two years of planned survey, landing at least once and returning to Earth in September 2023.

Source: Brown University

“What this paper shows is that you can get really different results depending upon the type of organic material you use to compare with and interpret the Ceres data,” said Hannah Kaplan, a postdoctoral researcher at the Southwest Research Institute who led the research while completing her Ph.D. at Brown. “That’s important not only for Ceres, but also for missions that will soon explore asteroids that may also contain organic material.”

"Organic molecules are the chemical building blocks for life. Their detection on Ceres doesn’t mean life exists there or ever existed there; non-biological processes can give rise to organic molecules as well. But because life as we know it can’t exist without organic material, scientists are interested in how it’s distributed through the solar system."

“What we find is that if we model the Ceres data using extraterrestrial organics, which may be a more appropriate analog than those found on Earth, then we need a lot more organic matter on Ceres to explain the strength of the spectral absorption that we see there,” Kaplan said. “We estimate that as much as 40 to 50 percent of the spectral signal we see on Ceres is explained by organics. That’s a huge difference compared to the six to 10 percent previously reported based on terrestrial organic compounds.”