Seven years and 4 billion miles after its launch, NASA’s OSIRIS-REx spacecraft has successfully dropped off a capsule containing a precious sample of one near-Earth asteroid — and is now on course to rendezvous with another one in 2029.
Rocket thrusters built at Aerojet Rocketdyne’s facility in Redmond, Wash., have been guiding the bus-sized probe every step of the way.
Today marked the climax of OSIRIS-REx — which stands for Origins, Spectral Interpretation, Resource Identification and Security-Regolith Explorer. The billion-dollar mission is designed to let scientists examine pristine stuff from a space rock that could shed light on the chemistry of the primordial solar system, and give them a better idea of the resources that could someday be gleaned from asteroids.
The sample was blasted away from a 1,600-foot-wide asteroid called Bennu back in 2020, four years after the spacecraft’s launch from Florida. Months later, the spacecraft began its two-year journey back toward Earth.
When the probe came within 63,000 miles of Earth, it sent an 30-inch-wide capsule containing the sample on a trajectory that brought it down through the atmosphere hours later.
The capsule took advantage of a heat shield to withstand temperatures of up to 5,000 degrees Fahrenheit during its 27,000 mph plunge. Then it deployed its parachute and floated down to a touchdown on the Defense Department’s Utah Test and Training Range at 8:52 a.m. MT (7:52 a.m. PT).
Dante Lauretta, the OSIRIS-REx mission’s principal investigator, told reporters that he “literally broke into tears” when he heard that the parachute had deployed as planned. “That was the moment I knew we made it home,” he said.
A recovery team rode helicopters out to the landing site and carefully secured the capsule for processing. The sample, which is thought to amount to as much as 8.8 ounces (250 grams) of asteroid rubble, is due to be flown to NASA’s Johnson Space Center in Texas on Monday for an initial round of study.
“The real science is just beginning,” Lauretta said.
Eileen Stansbery, who’s in charge of Johnson Space Center’s Astromaterials Research and Exploration Science Division, said she expected more than 200 researchers on the mission’s science team to start studying the material within the next few weeks. “These samples are an amazing treasure trove for generations,” she said.
Even as the capsule fell toward Earth, the OSIRIS-REx mothership fired its Aerojet-built thrusters to dodge the planet and get set for the journey to another asteroid called Apophis.
Apophis grabbed the headlines years ago when initial observations of its orbit held out a slight chance of a collision. (Additional observations ruled out the threat.)
The first maneuver toward Apophis is due to take place in a month. If all goes according to plan, the spacecraft will conduct an 18-month survey of the asteroid just after its close approach to Earth in April 2029.
In recognition of the transition, the main spacecraft’s mission has a new name: OSIRIS-APEX — with APEX standing for “Apophis Explorer.”
Bill Cahill, Aerojet’s OSIRIS-REx program manager, said the spacecraft’s thruster system was critical to the mission’s success. He highlighted the system’s performance during the sample collection operation in 2020.
“There’s so little gravity around Bennu that even the smallest of pulses from a thruster would have a great impact on OSIRIS-REx’s orbit around the asteroid,” he said in a news release. “The thruster had to be highly specialized so we didn’t throw the spacecraft out of orbit as the necessary maneuvers were conducted.”
By all accounts, the thrusters performed just as well today.
“The complexity of the operation and our ability to provide thrusters that can be an integral part of maneuvers that help achieve science goals is incredibly rewarding,” Cahill said. “The delivered regolith samples will teach us a phenomenal amount about the asteroid, and more importantly, the origins of our solar system, and this is something our entire team can be proud of.”
OSIRIS-REx follows up on earlier sample return missions — including Stardust, which brought back samples of cometary and interstellar dust in 2006 under the leadership of University of Washington astronomer Don Brownlee; and Hayabusa 1 and Hayabusa 2, a pair of Japanese missions that returned smaller samples of asteroids in 2010 and 2020.
After today’s touchdown, NASA Administrator Bill Nelson heralded OSIRIS-REx as the beginning of a new chapter in the study of near-Earth objects. “This mission proves that NASA does big things,” he said. “It wasn’t ‘Mission Impossible,’ it was ‘The Impossible Became Possible.'”
Chris Lewicki, who once served as the president and “chief asteroid miner” for Redmond-based Planetary Resources, said his heart was pounding as he watched the OSIRIS-REx sample return capsule descend.
“I look forward to the day when a human has taken a journey as long and interesting as the OSIRIS-REx capsule which has just returned to Earth,” Lewicki said in a post to X / Twitter. “The human would be a better conversationalist. These samples will require some study to tell their tales.”
Planetary Resources faded away in 2018 due to lack of funding, but Lewicki is still involved in the field of asteroid exploration. He’s a member of the standing review board for NASA’s Psyche mission, which is due to launch a probe toward a metal-rich asteroid named Psyche next month. He’s also working on a project for the XPRIZE foundation that could result in the creation of a prize for orbital debris removal.
Lewicki told GeekWire that analysis of the OSIRIS-REx sample could give scientists — and future asteroid miners — fresh clues as to the composition of carbonaceous asteroids, including the presence of hydrated minerals, silicates and metals that could help fuel a 21st-century space economy.
“It’s the very stuff that we’d be interested in,” Lewicki said.
