NASA Researchers Make Surprising Discovery in Rock Sample from Asteroid Bennu

Initial analyses of samples from the asteroid Bennu are revealing more about its past. It's a surprise to research.

WASHINGTON, D.C. – In the fall of 2023, NASA’s OSIRIS-REx space probe returned rock samples from the asteroid Bennu to Earth. The asteroid rock, unchanged by its entry into Earth’s atmosphere, has been under analysis for months. Now, a research team led by Dante Lauretta, principal investigator at the NASA-Osiris-Rex mission makes surprise discovery on Bennu rock.

In addition to the original “ingredients” that formed the solar system (carbon, nitrogen, and organic compounds), the soil sample from the asteroid also contains magnesium and sodium phosphate. This came as a surprise to the research team, as remote sensing data collected by the space probe on the asteroid Bennu had not previously suggested this. For the researchers, the presence of sodium and magnesium phosphate is an indication of the asteroid’s past.

Asteroid Bennu appears to have a 'watery past'

“The presence and condition of phosphate, as well as other elements and compounds, on Bennu suggests a watery past for the asteroid,” Lauretta explains in an article. NASA AdvertisementBennu may have been part of a wetter world. However, this hypothesis still needs further investigation. Stady Published in the specialized journal Meteorites and Planetary Science Published.

Jason Durkin, the mission’s project scientist and co-author of the study, is thrilled: “OSIRIS-REx has given us exactly what we were hoping for: a large sample of the parent asteroid, rich in nitrogen and carbon, and from a formerly wet world.” Further analysis of the asteroid samples has given the research team new insights into the asteroid’s composition.

Asteroid Bennu holds a surprise for researchers

Mostly clay minerals (especially serpentine) were found in the sample. This type of rock is found on Earth at mid-ocean ridges, where material from the Earth’s mantle meets water. This reaction not only creates clay, but also a variety of minerals such as carbonates, iron oxides, and iron sulfides. But the most surprising discovery was the presence of water-soluble phosphates. These compounds are the biochemical components of all known life on Earth today.

“The sample we brought back from Bennu is the largest reservoir of unaltered asteroid material currently on Earth,” Lauretta is certain. The asteroid material has been preserved in its original state, neither melting nor solidifying since its formation, a true treasure trove of research, which is expected to yield more studies on Bennu in the coming years. (unpaid invoice)