Scientists are now examining bits and pieces plucked, bagged and tagged from asteroid Bennu, the cosmic mother lode, provided by NASA's Origin, Spectral Interpretation, Resource Identification and Conservation – Regolith Explorer mission.
Known in short astro-speak as OSIRIS-REx, the seven-year mission began on Sept. 24, 2023 brought the material home in a sample return canister that was parachuted into a remote Utah area by the Department of Defense. Testing and training range. Those distant samples are believed to contain remnants from the formation of the Solar System 4.5 billion years ago.
Space.com caught up with two of the leading scientists involved in dissecting what light those dark asteroid particles are shedding, sorting out how these exported materials from Bennu came to be. But what insights do they hold about the origin of worlds in our solar system, including Earth?
Related: NASA's 1st asteroid sample rich in carbon and water, OSIRIS-REx team finds
An ancient reservoir
This scene is an astromaterial analysis by the University of Arizona's Kuiper-Arizona Laboratory. Researchers there use instruments to study what the OSIRIS-REx collections tell them, down to the atomic scale.
Initially, University of Arizona scientists obtained 200 milligrams — about seven-thousandths of an ounce — of the Bennu asteroid sample for analysis.
„We have 1,000 particles larger than half a millimeter, 28 particles larger than a centimeter, and the largest particle is 3.5 centimeters,” said Dante Lauretta of the University of Arizona, principal investigator of OSIRIS-REx. „So a great set full of great stones.”
Bennu samples contain abundant water in clay-like minerals and are also rich in carbon, nitrogen, sulfur and phosphorus. The OSIRIS-REx samples represent the largest pristine reservoir of such material on Earth.
„We're going to be busy for a long, long time,” Lauretta told Space.com. „It's a huge sample size for us,” he said, adding that Bennu's samples are now being studied around the world.
Weird and weird
What was discovered will be detailed next month at the 55th Lunar and Planetary Science Conference in The Woodlands, Texas. More than 70 scientific publications have been submitted at that prestigious meeting, Lauretta said. „Starting March, all these will be rolled out across the world. So the team is working furiously,” he said.
An initial finding was that the asteroid material under study „looked different and different isotopically than anything in our meteorite collection, which is exciting,” Lauretta said. „If we rely on meteorites, there's a whole area of objects that we'll never have access to,” Lauretta added.
Most meteorites that survive fiery fall through Earth's atmosphere are fragments of asteroids. But pinpointing the space rock from which they originated is not an easy task.
OSIRIS-REx samples meteorites with phosphate crusts that have never been seen before, Lauretta said. These high concentrations of phosphate have been found on extraterrestrial ocean worlds, he said.
For example, Saturn's moon Enceladus contains phosphates, a key building block of life and in greater abundance than Earth's oceans.
„Asteroid Bennu may be a fragment of an ancient ocean world. That's still highly speculative, but this is the best way I can explain the origin of the object right now,” Lauretta said.
Connect the dots
Unraveling the history of asteroid Bennu has been a surreal endeavor, said Thomas Zega, a professor at the university's Lunar and Planetary Laboratory and scientific director for astrophysical analysis at the school's Khyber-Arizona Observatory.
Zeiga points to the decades that predated the OSIRIS-REx mission, from a complete project to intensive study of asteroid samples at the laboratory.
„Honestly, a day rarely goes by where I don't consider myself incredibly lucky to actually be doing this for a living,” Zega told Space.com. „I pinch myself. It's a blessing.”
The OSIRIS-REx mission has been a spectacular success by any definition, Zega said, adding, „Now we're able to use some of the most sophisticated analytical instruments on the planet to measure samples, which is pretty remarkable.”
Missions like OSIRIS-REx, in addition to teaching scientists about Bennu's origin, Zega noted, „are really helping to connect the dots between other meteorites in our terrestrial collection, and they may have come from asteroids,” he said. in the asteroid belt between Mars and Jupiter.”
Jega was a member of the „Quick Look” team that participated in the opening of the OSIRIS-REx sample return capsule after it was delivered to NASA's Johnson Space Center in Houston, Texas.
What the curation team experts discovered was a coating of fine dust from the sample maneuver on the avionics deck returned to Bennu and on the outside of the Touch-and-Go Sample Acquisition Mechanism (TAGSAM) – the end of the OSIRIS-REx robotic arm, an anomaly like an air filter, trapped most of the Bennu fragments.
One aspect of Jega's surreal encounter with Bennu was to depart from Texas and fly back to Arizona with a pre-arranged, small-scale sample from the asteroid.
After all, Zega's express courier duties are due to the University of Arizona's 20 years of work moving OSIRIS-REx from orbit to ballistic entry of asteroid material.
Cover of darkness
„There was no way it was going in checked baggage! It went into my bag and I took it on the plane. It was a small amount of material, sealed in a bag that was sealed in a vial filled with nitrogen. So it was all protected,” Zega recalled.
After landing in Tucson at night, the first thing Zega did was rush the sample into a dry nitrogen box in the university lab for safety and security.
„Then I went home, had dinner and went to sleep,” Jega recounted.
Jega said jokingly that the whole thing was under cover of darkness. „No one was the wiser that someone brought the first sample from the first NASA asteroid sample to Tucson,” he said.
Last month, Jan. On the 10th, NASA curators fully opened the OSIRIS-REx TAGSAM head filled with Bennu bits. That final step was slow in coming because of two complicated fasteners that prevented see-through of the entire inventory of asteroid collections.
Now On Tab is releasing a catalog of all Bennu samples later this year, giving scientists and institutions around the world the ability to submit requests to study bites from the Bennu spacecraft.
Meanwhile, Lauretta and Zega, along with colleagues, are busily evaluating the Bennu samples.
Teams of university students and faculty use a wide range of skills, from optical and electron microscopes to newly acquired equipment.
A powerful NanoSims tool is running and provides a fascinating look at isotopes (different variations of atoms) to explain how each specific element in the Bennu sample formed.
„We have a lot of cool things coming up in the next few months,” Lauretta said. „So wait.”
„Oddany rozwiązywacz problemów. Przyjazny hipsterom praktykant bekonu. Miłośnik kawy. Nieuleczalny introwertyk. Student.