Tasked with finding clues about origins of life on Earth, NASA’s OSIRIS-REx spacecraft scooped up pieces of a rugged, rubble-pile asteroid named Bennu in late 2020 and delivered them to Earth about two months ago. On Monday (Dec. 11), scientists got their first detailed description of a few of that extraterrestrial collection.
“We definitely have hydrated, organic-rich remnants from the early solar system, which is precisely what we were hoping after we first conceived this mission almost 20 years ago,” Dante Lauretta, the mission’s principal investigator, said on the American Geophysical Union (AGU) conference being held this week in California and online. “I fully expect the cosmochemistry community goes to go to town on this.”
Lauretta, a professor of planetary science and cosmochemistry on the University of Arizona, said the bits of the traditional asteroid which were retrieved up to now are from the outer lid of the sample capsule and are wealthy in carbon and organic molecules. All of the particles are very dark in color and consist of centimeter- and millimeter-sized “hummocky boulders” which have a rough “cauliflower-like texture,” said Lauretta. “They cling to every thing we touch them with.”
The OSIRIS-Rex spacecraft was designed to keep up a correspondence with Bennu for six seconds, however it ended up plunging 1.6 feet (0.5 meters) into the asteroid’s surface for 17 seconds as a substitute. A victim of its own success, the probe dug out a lot material that particles began leaking out of the sample collector’s head — but they were still protected inside its outer lid. On Monday, Lauretta blamed a 1.3-inch (3.5 cm) Bennu stone that appeared to have jammed open a small flap on the pinnacle and let the fabric escape into the lid.
Two faulty fasteners proceed to prevent technicians from removing the lid to access and catalog the majority of the collected sample that is still trapped throughout the head. While they wait for brand spanking new tools to be approved to be used on the dear rocks, they’re using tweezers to select tiny rocks through the partially open flap, totaling the collected material to 70.3 grams (0.07 kg) — higher than the mission’s mandated minimum of 60 grams (0.06 kg).
A few of that material was shipped for spectral evaluation on the NASA-supported Reflectance Experiment Laboratory (RELAB) facility in Rhode Island, while one other batch was sent to the Natural History Museum in London. Initial findings using spectroscopy, a scientific technique that reveals a cloth’s makeup by studying the way it reflects different wavelengths of sunshine, show a dominant spectral signature in blue. This azure hue is currently unexplained but may mean the space rocks contain much more water than scientists initially predicted, Lauretta said, adding that more results shall be shared at a scientific meeting next spring.
The fabric also hosts high amounts of magnesium, sodium and phosphorus, a mixture that up to now puzzles the team.
“I have been meteorites for a very long time, and I’ve never come across anything like that,” said Lauretta. “It is a head-scratcher at once. What is that this material?”