 The OSIRIS-REx capsule and its parachute shortly after landing at the Utah Test and Training Range on Sunday. (credit: NASA/Keegan Barber) |
A capsule’s fall marks the start of Asteroid Autumn
by Jeff Foust
Monday, September 25, 2023
Most scientists leading planetary science missions attend the launch of their spacecraft, seeing them off on journeys across the solar system. Few scientists, though, are present for those missions’ landings.
| “I wanted to personally be out there to greet these pieces of Bennu to our home planet, welcome them to the curation facility at Johnson Space Center and get them ready for the adventure we’re about to put them on,” said Lauretta. |
Dante Lauretta was the exception. The principal investigator for NASA’s OSIRIS-REx (whose full name, rarely used, is Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer), Lauretta was in Florida for the launch of the spacecraft in September 2016 and, seven years later, in Utah when a capsule from the spacecraft returned from the near Earth asteroid Bennu to land on a military test range southwest of Salt Lake City.
“I wanted to personally be out there to greet these pieces of Bennu to our home planet, welcome them to the curation facility at Johnson Space Center and get them ready for the adventure we’re about to put them on,” he explained at a briefing a few weeks before the September 24 landing.
And, about an hour after the capsule touched down—and after others confirmed there were no hazards from the spacecraft itself or from potential unexploded ordnance in the range—Lauretta and a couple others approached the capsule, inspecting it. “It was like meeting an old friend that I hadn’t seen for a long time,” he said later in the day, adding he resisted the urge to hug it. It was, after all, covered in soot from its reentry.
The landing concluded a successful mission to bring back samples from Bennu for analysis in laboratories around the world. Lauretta and others on the mission estimate that the capsule contains 250 grams of material from Bennu, far more than the mission’s requirement of 60 grams.
There was, though, a little bit of drama during the capsule’s landing. NASA has stated that the capsule should land at 8:55 a.m. local time, 13 minutes after it started reentry near the California coast. Yet the capsule touched down three minutes early, and NASA later said that that the main parachute opened at a higher altitude than expected: about 6,000 meters versus the planned 1,500.
At a post-landing briefing, it was unclear how well a drogue parachute, set to open at a higher altitude, had performed. There was no visual confirmation, including from high-altitude aircraft used for tracking the reentry, that the drogue had deployed, but project officials later said that they assume the drogue had deployed since that was a requirement for the main parachute to deploy.
Whatever happened, though, did not affect a safe landing: the capsule touched down upright, having made only a very small depression in the ground. “Something in our sequence may or may not have behaved itself exactly the way we expected it to, but the subsequent things in the sequence made up for it,” said Tim Priser, chief engineer for deep space exploration at Lockheed Martin, which built the OSIRIS-REx spacecraft.
The capsule landed about eight kilometers east of the target, but well within a landing ellipse of 12 by 30 kilometers. Mike Moreau, deputy project manager for the mission at NASA’s Goddard Space Flight Center, said that appeared to be based on atmospheric conditions and was predicted in advance of reentry, and not linked to any issues with the parachute.
The landing was a relief for Lauretta, who was on a helicopter during reentry. The callouts of the capsule’s altitude didn’t seem right, he recalled, but he wasn’t sure if that was an issue with the capsule or simply the limited communications available in the helicopter. “I was mentally preparing myself for the worst-case scenario,” he said.
Then came the call that the main parachute had opened. “That’s when I just emotionally let it go,” he said, knowing that, with the parachute open, the capsule was headed to a nominal landing. “Tears were streaming down my eyes. That was the only thing I needed to hear.”
| “The samples waited for more than four billion years for humans to study it, and if it takes us a little longer, I think we’ll be okay,” Glaze said of the effects of a government shutdown on processing Bennu samples. |
Shortly after Lauretta made his personal inspection of the capsule, it was transported to a temporary clean room at the Dugway Proving Ground to remove elements like the backshell and heat shield. The canister containing the samples was scheduled to fly to the Johnson Space Center the next day, going into a dedicated curation facility not far from where the Apollo lunar samples are stored, where the canister will be opened and analysis of its contents begins.
 Members of the OSIRIS-REx recovery team, including mission principal investigator Dante Lauretta (right), study the capsule after landing. (credit: NASA/Keegan Barber) |
The landing, just a couple days after the autumnal equinox, kicked off what NASA has dubbed “Asteroid Autumn.” The OSIRIS-REx samples are one of three events related to new or ongoing asteroid missions that the agency is highlighting through November.
The next is scheduled for October 5, when a Falcon Heavy rocket is scheduled to lift off from the Kennedy Space Center carrying Psyche, another asteroid mission that will travel to the metallic main belt asteroid of the same name. On November 1, NASA’s Lucy spacecraft, launched in October 2021 will fly by another main belt asteroid, Dinkinesh, on its way to the Trojan asteroids that lead and follow Jupiter in its orbit around the Sun.
Psyche was scheduled to launch in August 2022, but was delayed because of issues testing the spacecraft’s flight software, a symptom of more fundamental issues with the management of programs at the Jet Propulsion Laboratory uncovered by an independent review board (IRB) last fall.
The problems with both Psyche and JPL have been resolved. “The IRB believes the response to our Psyche project and JPL institution findings and recommendations to be excellent,” Tom Young, who chaired that committee, said in June. “We believe that Psyche is on a positive course for an October 2023 launch.”
The biggest threat to Psyche now is something outside of NASA’s hands: the threat of a government shutdown. The new fiscal year starts October 1 and Congress so far has failed to pass a stopgap spending bill, called a continuing resolution (CR), to keep the government running while it hammers out full-year spending bills. Several efforts to pass spending bills in the House last week failed, victims of internecine Republican strife.
NASA is continuing preparations for the Psyche launch, but it’s unclear how a government shutdown just days before the launch—at the start of a three-week launch window—would affect those plans. “In the past, NASA has been prepared to request a waiver for operations, essential mission and launch personnel to ensure that missions can meet their launch period, and we are certainly prepared to follow that same path here,” Lori Glaze, director of NASA’s planetary science division, said during a briefing about the mission in early September.
In past shutdowns, ongoing operations of missions have continued but those not yet launched have been stopped unless there is testing or other work that, if halted, would threaten hardware or public safety. Even if the launch does proceed, much of the publicity surrounding it might be halted.
A shutdown could also affect processing of the samples returned by OSIRIS-REx at that JSC curation facility. Glaze said last week that initial work on those samples, which NASA has been planning to show off at an October 11 event, could be suspended in the event of a shutdown.
In that scenario, she said, would ensure the samples “remain protected and safe” during the shutdown. “The samples waited for more than four billion years for humans to study it, and if it takes us a little longer, I think we’ll be okay.”
NASA’s planetary science program could use the good news provided by as asteroid sample return mission as it grapples with the challenges of Mars sample return. NASA released last week the final report of an independent review it commissioned this summer to look at the Mars Sample Return (MSR) program, and the results were grim.
“MSR was established with unrealistic budget and schedule expectations from the beginning,” the report stated. “As a result, there is currently no credible, congruent technical, nor properly margined schedule, cost, and technical baseline that can be accomplished with the likely available funding.”
| The report urged NASA to provide “a consistent and unified message to Congress, the scientific community, and to the public regarding MSR’s scientific and strategic importance to the nation.” |
The report found a “near zero probability” that the two MSR spacecraft, a NASA-led sample retrieval lander and ESA-led Earth return orbiter, could be ready in time for launches in 2027 and 2028 as currently scheduled. The earliest they could launch is 2030, with a total cost of $8–9.6 billion. That would require, though, spending more than $1 billion a year on MSR from 2025 through 2028, an amount that could knock the entire planetary program at NASA out of balance.
The report offered several alternatives, including shifting from one lander to two that could leverage the “skycrane” technology used on past missions, and delaying their launches to as late as the mid-2030s. Those would not change the total cost much, with the report estimating costs of $8–11 billion, but could decrease the peak spending to no more than $850 million a year in some scenarios.
The report did not recommend NASA give up on MSR, instead doubling down on the importance of returning samples, including those stored on the Perseverance rover itself. The cache of 10 samples left in a region called Three Forks, a contingency in case something happens to Perseverance, “is not an optimal sample set because it does not represent the full diversity of geologic environments along the rover’s traverse that could preserve signs of life,” the report concluded.
The report also urged NASA to provide “a consistent and unified message to Congress, the scientific community, and to the public regarding MSR’s scientific and strategic importance to the nation,” which includes, it noted, the soft power benefits of such a mission as China plans its own Mars sample return mission some time around 2030.
NASA responded by announcing it would delay a confirmation review for MSR, which would set formal cost and schedule goals for the program, that had been scheduled for this fall. The agency will instead review the independent report and develop recommendations for a path forward early next year.
Assuming MSR does go forward, that mission will likely conclude with a sample return capsule landing at the same Utah test range as OSIRIS-REx. Lauretta noted at the post-landing briefing that the landing was the culmination not just of seven years of flight operations but efforts dating back more than two decades, when Lockheed Martin and the University of Arizona decided to work together on an asteroid sample return mission that came OSIRIS-REx.
“I was there when it was nothing but a PowerPoint slide in a proposal that we were submitting to NASA,” he recalled. “We pulled it off, as incredible as it seemed all those years ago.”
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