A capsule from Bennu drops onto the Utah desert, a minute ahead of schedule
Seven years after launch, NASA's OSIRIS-REx spacecraft finally released its cargo. At 4:42 a.m. MDT on September 24, 2023, OSIRIS-REx ejected the sample return capsule, which later touched down at the Utah Test and Training Range at about 8:52 a.m. MDT at just 11 mph, one minute earlier than mission planners had predicted. A wiring mistake kept the drogue parachute from deploying at 100,000 feet, but the main chute opened anyway at 9,000 feet and held despite the extra speed. Helicopters lifted the capsule out by 10:15 a.m.
A NASA-led spacecraft, tracked by a University of Arizona-run science team, brought home the largest asteroid sample ever collected by any nation, more than twice the mission's goal. The touchdown gave American labs first crack at material scientists call a preserved sample of the solar system's early chemistry, Within two years, that work turned up amino acids and DNA's four nucleobases.
QWhy does a third-grader's asteroid name reference a heron rather than a mythological bird outright?
North Carolina third-grader Michael Puzio won a 2012 naming contest run by the University of Arizona, The Planetary Society, and the LINEAR Project, beating out more than eight thousand entries from students worldwide. Puzio proposed Bennu because the OSIRIS-REx spacecraft's extended TAGSAM sampling arm reminded him of the Egyptian deity Bennu, which mythology typically depicts as a heron. The asteroid had carried the placeholder designation 1999 RQ36 since its discovery by the LINEAR Project on September 11, 1999. Every surface feature later mapped on the asteroid, including craters, ridges, and boulders, was subsequently named after birds or bird-like mythological figures to match the theme Puzio started.
QHow close did OSIRIS-REx actually fly to Bennu before touchdown, and how does that compare to a famous comet mission?
OSIRIS-REx settled into orbit around Bennu at just 1.75 kilometers, later tightening to about 1 kilometer, a distance so close it set a record for the closest orbit of any celestial object by any spacecraft. That beat the European Rosetta probe's orbit of comet 67P/Churyumov-Gerasimenko, which held its distance at roughly 7 kilometers. At that tight radius around tiny Bennu, one full orbit took the spacecraft 62 hours to complete. Ground teams needed that proximity because Bennu's gravity is so weak that normal orbital mechanics used for planets or larger bodies simply do not apply the same way.
QWhat almost derailed the sample collection before the spacecraft ever touched Bennu's surface?
Engineers ran two full rehearsals before committing to the real touch-and-go maneuver, first descending to 65 meters above the Nightingale site on April 15, 2020, then to just 40 meters on August 11, 2020. The original collection date of August 25, 2020, got pushed back to October 20 to allow more preparation time. During the actual descent, the spacecraft fired minimal thrusters to avoid contaminating Bennu's surface with unreacted hydrazine propellant, and its solar arrays were locked into a Y-shaped configuration in case the spacecraft tipped up to 45 degrees on contact. The touchdown itself landed within 92 centimeters of the targeted spot, a margin of precision aimed at a crater roughly the size of a few parking spaces.
