NASA finds phosphate in samples of asteroid Bennu – DW – 06/28/2024

In order to study and gain more information about the formation and history of our solar system, on September 24, 2023, NASA’s OSIRIS-REx mission successfully returned samples of the asteroid Bennu to Earth.

After analyzing 121.6 grams of space rock, NASA scientists found that it contained sodium and magnesium phosphates, indicating that it may have originated on an oceanic world, according to a study published this Wednesday (06/26/2024). Journal of Meteoritics and Planetary Science.

“These results highlight the importance of collecting and studying material from asteroids like Bennu,” NASA said in a statement. Dante Lauretta, co-author of the paper and principal investigator of OSIRIS-REx at the University of Arizona.

Essential Components for Life

According to astronomers, the asteroid Bennu, which is relatively close to Earth, may provide several clues about the formation of the solar system because it existed when our cosmic neighborhood was formed.

And they were right: the researchers were able to determine that the Bennu samples contain carbon, nitrogen, organic compounds and other components necessary for life.

“This material contains the key to unraveling the complex processes of the formation of the solar system and the prebiotic chemistry that could have contributed to the emergence of life on Earth,” the expert adds.

Surprise detection of phosphate

Additionally, to the researchers’ surprise, the asteroid’s dust also contained sodium magnesium phosphate, suggesting that Bennu may have broken away from a small, primitive ocean world that has long since disappeared.

“OSIRIS-REx gave us exactly what we expected: a large, pristine, nitrogen- and carbon-rich asteroid sample from a previously wet world,” said Jason Dworkin, co-author of the paper.

“The presence and state of phosphates, along with other elements and compounds in Bennu, suggest an aquatic past for the asteroid. Bennu may have been part of a wetter world. Although this hypothesis requires additional research,” adds Lauretta.

Other aspects of interest

In 2020, the Japan Aerospace Exploration Agency’s (JAXA) Hayabusa2 mission returned samples from the asteroid Ryugu to Earth. Although phosphates were detected then, the magnesium and sodium phosphates now found are distinguished by their purity and grain size.

Additionally, the predominant component of asteroid Bennu is magnesium-bearing layered silicates, mainly serpentine and smectite, rock types commonly found on Earth’s oceanic ridges.

“The data we present here is just the tip of the iceberg: it is likely that there is more about the sample that we do not know,” the researchers conclude.

Edited by Jose Urreiola, using information from NASA, Space.com, and Meteoritics & Planetary Science.