Triumph in Utah: OSIRIS-REx Returns Home

After 7 years in space, and 3.8 billion miles traveled, NASA’s OSIRIS-REx Sample Return Capsule (SRC) completed a picture perfect touchdown on the muddy sands of the Utah Test and Training Range in Dugway, Utah, bringing a historic chapter of this mission to a close, and providing planet Earth with a piece of the asteroid Bennu. 

OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) was selected as part of NASA’s New Frontiers program in May 2011, the third mission in this “mid range” class. These missions aim to accomplish more than their smaller scale Discovery-class counterparts, but are targeted at lower costs than the larger Flagship class. Overall management, engineering and navigation for the mission is provided by NASA’s Goddard Space Flight Center, while the University of Arizona’s Lunar and Planetary Laboratory provides principal science operations. Dr. Dante Lauretta of the University of Arizona serves as the principal investigator of the mission, and directs the research team. Lockheed Martin Space Systems built the spacecraft and continues to provide mission operations. OSIRIS-REx was launched atop an Atlas V 411 on September 8th, 2016 from Cape Canaveral’s SLC-41, and separated 55 minutes later – sending the intrepid spacecraft towards asteroid Bennu and back.

At 22:13 UTC, on October 20th, 2020, OSIRIS-REx successfully touched down on Bennu, after months of orbital characterization – a careful study of the asteroid from orbit. Dr. Danny Glavin, the Sample Organics Analysis Working Group lead and Senior Scientist for Sample Return, noted that the asteroid looked quite different from how they had originally envisioned it, prompting the team to take additional time to assess the asteroid for a suitable landing site. The spacecraft touched down within 92 cm (36 in) of the target location, known as Nightingale. Despite initial concerns that the sample mechanism had malfunctioned, as material was seen spilling out of the sample cache, the team managed to stow the material collected and continue with their mission. After an assessment of precisely how much of Bennu the spacecraft had captured, the OSIRIS-REx team prepared the spacecraft for the next phase of the mission – the return cruise to Earth. On April 7th, 2021, OSIRIS-REx completed its final flyover of Bennu and began slowly drifting away from the asteroid. On May 10th, 2021, OSIRIS-REx departed Bennu and began its two-year journey to Earth with the asteroid sample. 

OSIRIS-REx remained largely dormant for its return journey towards Earth, while the teams at Lockheed Martin and NASA practiced extensively for the arrival of the SRC in Dugway. The combined team consists of 4 helicopters, a NASA Gulfstream jet, and the WB-57 Canberra high altitude research aircraft, used most commonly to track launches and landings of crew missions. In the days leading up to arrival, OSIRIS-REx used its onboard thrusters to line itself up on an intercept course with Earth, charging the batteries onboard the SRC to ensure that the vehicle would have the necessary power to maintain a pristine environment through the final leg of the journey. Early on September 24, 2023, the combined Lockheed Martin and NASA team completed a GO/NO GO poll for sample release. If there was any issue onboard, the teams could have elected to not release the capsule and wait for the next Earth flyby in 2025, on the way to asteroid Apophis. At 4:42 AM MDT, the spacecraft released the SRC, and subsequently began the 20 minute diversion maneuver to fly by the planet. 

With the spacecraft safely on its way to a 484-mile close approach, the SRC began the next phase of flight, known as Entry Descent and Landing – EDL. At 8:42 AM MDT, the SRC began entry, hitting the top of the Earth’s atmosphere at 433,00 feet in altitude, traveling 27,650 miles per hour, significantly faster than missions returning from low Earth orbit. The high altitude WB-57 used its suite of infrared cameras and sensors to track the capsule, guiding the recovery teams towards the projected landing site.  At approximately 8:50 AM MDT, the main chute of the SRC opened, albeit higher than expected at around 20,000 feet, rather than the 5,000 feet projected, due to the capsule meeting deceleration targets earlier than planned. At approximately 8:53 AM MDT, the capsule touched down on the desert floor – ready to be recovered by scientists and studied by teams around the world. In space, OSIRIS-REx became OSIRIS-APEX, continuing towards a daring encounter with asteroid Apophis in 2029. 

Following an assessment by the recovery teams, and careful documentation of the landing site, the work to get the SRC and its precious samples to the cleanroom could begin. Dr. Dante Lauretta and his team landed near the capsule approximately an hour after touchdown, and began to prepare the spacecraft for transport back to the temporary clean room facility. Due to the size and shape of the capsule, the decision was made during the design phase of the mission to carry the vehicle underneath one of the recovery helicopters, using a 100-foot-long line. Following successful bagging and securing of the sample, the helicopter teams departed the site, with one remaining behind to continue to document the condition of the sample site. After departing, the crew made their way back across the landing area, before delivering the samples to the mobile quarantine facility set up at Dugway Proving Ground. The samples will remain at Dugway for approximately 2 days before departing for Johnson Space Center on Tuesday, September 26. 

Upon successful confirmation of touchdown, the atmosphere at the recovery site was electric. Members of the OSIRIS-REx team from NASA, the University of Arizona and Lockheed Martin, having poured their hearts and souls into this mission for nearly two decades, were tremendously relieved to have their precious cargo on the ground. Dr. Lauretta, speaking to the press after completing operations at the landing site, said that the moment was bittersweet: “I wasn’t able to sleep at all last night, and I’ve been waiting for this day since the beginning.” For mission planners, the landing of the SRC was the end of one phase, and for scientists on the ground, the arrival today was only the beginning.

Edited by Beverly Casillas, special thanks to Matt Dahle