Osiris-Rex landing site.
HOUSTON—The Osiris-Rex sample canister with material gathered from the surface of the asteroid Bennu was flown on Sept. 25 from its landing site in the Utah desert to NASA’s Johnson Space Center (JSC).
The cannister containing the more than 4 1/2-billion-year-old contents is to be opened at JSC to begin the first in an anticipated decade-long series of scientific studies.
The C-17 military transport aircraft landed at Houston’s Ellington Airport about 2 p.m. EDT for off-loading and a short drive to JSC’s Astromaterials Research and Exploration Services (ARES) curation facilities. The facilities are home to Apollo Moon rocks, comet and solar wind particle samples and meteorites already in curation and under analysis.
The recently constructed curation facility for Osiris-Rex was developed to preserve the estimated 250 grams (8.8 oz.) of surface material extracted from Bennu on Oct. 20, 2020. The facility will protect the material from earthly contaminants that could interfere with efforts to assess the nature of the material as well as the mineral and chemical composition and other factors that could provide new insight into how the Solar System’s planets formed and obtained the organics that provided the building blocks for life.
The 32-in.-wide, 110-lb. sample capsule was released by the Osiris-Rex spacecraft early Sept. 24 for re-entry into the Earth’s atmosphere and a parachute-assisted landing. The capsule landed at 10:52 a.m. EDT in the Utah desert at the Department of Defense’s Test and Training Range. Quickly recovered, the capsule was flown a short distance by helicopter to a temporary on-site clean room. There, the unopened sample canister containing the soil and pebbles from Bennu was removed from the capsule and placed in a shipping container along with surface samples of the Utah desert collected from the landing site for the flight to JSC.
“We have a busy week ahead of us,” Dante Lauretta, the University of Arizona planetary scientist who serves as the mission’s principal investigator, told a post-landing NASA news briefing on Sept. 24. “We are flying to Houston tomorrow morning at the crack of dawn, and then Tuesday [Sept. 26] we hope to get that canister open. I expect we will see some dust, and we have a plan to sample that dust and get it into the science instruments at JSC right away, just to see did we bring back what we thought or is it something completely different. Knowing Bennu, it might be a little of both.”
As the Osiris-Rex mission was launched on Sept. 8, 2016, Bennu was classed as a near Earth rubble pile asteroid, the product of a long-ago collision between two planetary bodies. It left a “rubble pile” asteroid held loosely together by gravity and with a boulder-strewn surface. It appeared to be rich in organics with materials chemically altered by liquid water in the distant past.
Between the time Osiris-Rex arrived at Bennu in December 2018 and when it touched down to collect its sample, the spacecraft conducted a lengthy, low-altitude reconnaissance to select the sample site. When the spacecraft touched down briefly to gather sample materials, its Touch and Go Sample Mechanism (Tagsam) plunged to a surprising depth before the probe lifted off.
It is some of that loose material on Tagsam and on the inside of the canister that will likely be initially analyzed.
“We have a great suite of analysis planned,” Lauretta said. “Did we accurately assess the bulk mineralogy and chemistry of the surface of the asteroid? Did our remote sensing instruments work? Did our data processing lead us to the right conclusions? Are there clay minerals? Are there carbonate minerals? Are there organic molecules? Do we see iron oxides and the other things we predicted?”
There could well be surprises, he predicted, a key factor in a decade’s long strategy for preserving much of the sample material so that it can be studied in the future as laboratory instrumentation technology continues to mature and complementary planetary science discoveries unfold.
The Japanese and Canadian space agencies, which partnered with NASA on Osiris-Rex, will receive shares of the sample material. The mission sample analysis team includes more than 200 representatives from more than 35 global science institutions.
“Osiris-Rex is about the science, but it’s also about the legacy and the legacy is that long-term collection, and we want to work hand in hand in science and curation to make sure both of those are achieved in a timely manner,” Lauretta said.
Prior to the Sept. 24 landing, NASA scheduled an Oct. 11 news briefing to discuss an initial analysis of the sample materials.
During the Sept. 24 post-landing news briefing, Lori Glaze, the director of NASA’s Planetary Science Division, said the agency is working to ensure that a looming possible federal government shutdown does not interrupt critical sample processing activities.
“As far as the sample, we are committed to the processes that Dante mentioned and ensuring that those samples are kept secure and safe for prosperity,” Glaze said. “So we will assure they are safe. There may be a little bit of delay in the science analysis. We will make sure we step back as we are told to do, but we will assure that they are safe.”
The significance of the pledge is evident in the challenges faced by the Japan Aerospace Exploration Agency (JAXA) in the first asteroid sample return missions, Hayabusa and Hayabusa 2. Launched in May 2003, Hayabusa overcame a succession of mission difficulties to return less than a gram (0.035 ounces) of surface material from the asteroid Itokawa on July 13, 2010. Launched in December 2014, Hayabusa 2 returned 5 grams (0.176 oz.) of the asteroid Ryugu to Earth, also in remote Australia, on Dec. 6, 2020.
JAXA will receive some of the material from Bennu in return for providing NASA with a small portion of the fragments from Ryugu.
