[Rockhounds] ‘Head-scratcher’: first look at asteroid dust brought to Earth offers surprises

[Kreigh Tomaszewski]

In the two and a half months since NASA’s first asteroid sample-return
mission landed safely on Earth
<https://www.nature.com/articles/d41586-023-02954-2>, technicians have
carefully plucked more than 70 grams of asteroid dust and pebbles from the
outside of the spacecraft’s canister. That’s more than ten times the amount
ever brought back from an asteroid, and more than NASA declared necessary
to call the mission a success. Some of the pebbles even seem to contain a
combination of chemical elements that is puzzling researchers.

But these early discoveries are still a long way from where planetary
scientists had hoped to be after the 24 September touchdown. Last month,
researchers at the Johnson Space Center in Houston, Texas, discovered that
two of the 35 screws that fasten the lid of the sample-return canister
couldn’t be opened — blocking access to the remainder of the space rock.
Curators used tweezers to pull out what they could, but NASA is now making
new screwdrivers so it can get into the equipment it flew billions of
kilometres across the Solar System to the asteroid Bennu and back.

Until then, “it’s kind of like Schrödinger’s sample”, said Dante Lauretta,
a planetary scientist at the University of Arizona in Tucson who heads
scientific analysis for OSIRIS-REx. “We don’t know what’s in there.”
Lauretta spoke at a meeting of the American Geophysical Union in San
Francisco on 11 December where he was presenting the first results from the
mission.

Still, there’s plenty of science to do on the 70.3 grams that technicians
have managed to extract so far. Early analysis suggests that the Bennu
fragments are rich in volatile chemical elements preserved in the deep
freeze of space since the Solar System’s birth more than 4.5 billion years
ago. “This alone makes the whole mission worthwhile,” Lauretta said. “We
now have abundant pristine material” from the dawn of the Solar System.

https://www.nature.com/articles/d41586-023-03978-4