Bennu asteroid sample contains carbon, water, according to first ‘quick-look’ tests

12 Oct 2023

NASA’s headline-grabbing investigations involved SEM, infrared inspection, X-ray tomography, and chemical tests.

Initial studies of the 4.5-billion-year-old asteroid Bennu sample collected in space and brought to Earth by NASA show evidence of high-carbon content and water, which together could indicate the building blocks of life on Earth may be found in the rock.

NASA announced the news on Wednesday, October 11th, from its Johnson Space Center in Houston where leadership and scientists showed off the asteroid material for the first time since it landed in Utah, on September 24th.

This finding was part of a preliminary assessment of NASA’s OSIRIS-Rex (Origins, Spectral Interpretation, Resource Identification and Security – Regolith Explorer) science team.

“The OSIRIS-REx sample is the biggest carbon-rich asteroid sample ever delivered to Earth and will help scientists investigate the origins of life on our own planet for generations to come,” said NASA Administrator Bill Nelson.

“Almost everything we do at NASA seeks to answer questions about who we are and where we come from. NASA missions like OSIRIS-REx will improve our understanding of asteroids that could threaten Earth while giving us a glimpse into what lies beyond. The sample has made it back to Earth, but there is still so much science to come – science like we’ve never seen before.”

‘Bonus material’

Although more work is needed to understand the nature of the carbon compounds found, the initial discovery “bodes well for future analyses of the asteroid sample,” said NASA’s statement.

The goal of the OSIRIS-REx sample collection was 60 grams of asteroid material. Curation experts at NASA Johnson, working in new clean rooms built especially for the mission, have spent 10 days so far carefully disassembling the sample return hardware to obtain a glimpse at the bulk sample within.

When the science canister lid was first opened, scientists discovered bonus asteroid material covering the outside of the collector head, canister lid, and base. There was so much extra material it slowed down the process of collecting the primary sample.

“Our labs were ready for whatever Bennu had in store for us,” said Vanessa Wyche, director, NASA Johnson. “We’ve had scientists and engineers working side-by-side for years to develop specialized gloveboxes and tools to keep the asteroid material pristine and to curate the samples.”

‘Quick look’ methodology

Within the first two weeks of OSIRIS-Rex’s landing, scientists performed “quick-look” analyses of its initial material, collecting images from a scanning electron microscope, infrared measurements, X-ray diffraction, and chemical element analysis.

X-ray computed tomography was also used to produce a 3D computer model of one of the particles, highlighting its diverse interior. This early glimpse provided the evidence of abundant carbon and water in the sample.

“We are unlocking a time capsule that offers us profound insights into the origins of our solar system,” said Dante Lauretta, OSIRIS-REx principal investigator, from the University of Arizona, Tucson. “The bounty of carbon-rich material and the abundant presence of water-bearing clay minerals are just the tip of the cosmic iceberg.”

For the next two years, the mission’s science team will continue characterizing the samples and conduct the analysis needed to meet the mission’s science goals. NASA will preserve at least 70% of the sample at Johnson for further research by scientists worldwide, including future generations of scientists.

As part of OSIRIS-REx’s science program, a cohort of more than 200 scientists around the world will explore the regolith’s properties, including researchers from many U.S. institutions, NASA partners JAXA (Japan Aerospace Exploration Agency), CSA (Canadian Space Agency), and other scientists from around the world.

Video explainer of OSIRIS-Rex mission