The tasting mechanism on NASA’s OSIRIS-REx spacecraft is packed with specimens captured from asteroid Bennu previously this week– so full that some of the rocks are floating out into space.
Officials said Friday they will stow the samples inside the mission’s Earth return capsule quicker than prepared to minimize the loss of asteroid material.
” We had an effective sample collection attempt, almost too successful,” said Dante Lauretta, the mission’s principal investigator from the University of Arizona. “Product is getting away, and we’re accelerating stow as a result of that.”
NASA’s $1 billion Origins, Spectral Interpretation, Resource Recognition, Security, Regolith Explorer aims to become the first U.S. spacecraft to complete a round-trip journey to an asteroid.
After a nearly two-year close-up survey of asteroid Bennu– a clump of rock measuring a 3rd of a mile (500 meters) broad– the OSIRIS-REx spacecraft came down to the airless world Tuesday for a celestial smash and grab. Its objective was to record a minimum of 2.1 ounces, or 60 grams, of pebbles, rock fragments and dust particles for return to Earth.
Researchers in sophisticated terrestrial labs will scrutinize the asteroid samples, which may contain carbon-rich organic particles and other minerals consisting of water. Both types of specimens were part of the primitive soup of active ingredients that seeded life on Earth.
Data and images relayed to Earth from OSIRIS-REx earlier this week indicated the spacecraft carried out as planned, with its Touch and Go Sample Acquisition Mechanism, or TAGSAM, robotic arm contacting the asteroid for 6 seconds Tuesday. A high-pressure bottle of nitrogen gas at the end of the 11- foot (3.4-meter) arm fired to require surface material from Bennu into a collection chamber, imitating a reverse vacuum.
The head at the end of the TAGSAM arm is about the size of a supper plate. The OSIRIS-REx spacecraft and its tasting system were designed and constructed by Lockheed Martin.
OSIRIS-REx pulsed thrusters to remove from the asteroid after six seconds, officials said.
Lauretta said Friday he is “highly confident” the sample collection attempt achieved success, and that it gathered “abundant mass, absolutely proof of hundreds of grams of material, and possibly more.”
” My big issue now is that the particles are leaving since we’re almost a victim of our own success here,” Lauretta said Friday afternoon in a teleconference with press reporters.
Ground groups got their very first look of the sample collection device with a series of images downlinked by the spacecraft Thursday. OSIRIS-REx moved the robotic arm into position for a close-up view by the objective’s sample camera, or SamCam.
” We took a look at the sample head, and it has lots of sample product, far more than 60 grams,” said Thomas Zurbuchen, associate administrator for NASA’s science mission directorate.
” There is a lot in there that the diaphragm that was supposed to keep the sample in is stuck open, and we’ve observed a few of the sample pieces getting away into area,” Zurbuchen said. “Therefore, now time is of the essence.”
Lauretta stated the images showed around five rocks lodged in the opening of the sample collection chamber. The particles are right at the size limitation to go into the sampling mechanism, and they appear to have actually wedged open a mylar flap, which functions as a lid on the sample head.
” data-lazy-type=”iframe” src=”data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7″>< img alt="" data-lazy-src=" “data-lazy-type =” iframe “src=” information: image/gif; base 64, R0lGODlhAQABAIAAAAAAAP/// yH5BAEAAAAALAAAAAABAAEAAAIBRAA7 “>
The motion of the TAGSAM arm Thursday most likely contributed to the loss of some of the samples observed in the images beamed back to Earth. Lauretta approximated that
5 to10 grams of” flaky “material could have been lost from the TAGSAM head Thursday” in a worst-case price quote “as the samples were interrupted by the arm’s motions.
With the robot arm still, supervisors have actually seen less evidence of a particle cloud around the spacecraft in images from OSIRIS-REx’s star tracker navigation video camera.
Mission supervisors originally arranged a sample mass measurement Saturday, during which OSIRIS-REx would extend its tasting arm as it went into a spin to measure the spacecraft’s moment of inertia. Ground groups planned to compare the information to a similar maneuver performed before OSIRIS-REx gathered its sample from Bennu to estimate the mass of fresh asteroid product inside the TAGSAM head.
If the estimate showed OSIRIS-REx had captured more than 60 grams of asteroid samples, strategies called for stowage of the specimens inside the return provider in early November. If not, there was a chance for OSIRIS-REx to try another sample collection run on Bennu in January.
With the images downlinked Thursday, officials are now sure the spacecraft grabbed enough of a sample to satisfy the mission’s minimum success criteria.
” I made the decision to forego the sample mass measurement, and asked the team to prepare right away to do the analysis to see whether we’re all set for stow,” Zurbuchen stated.
NASA revealed the Friday afternoon press rundown less than hour ahead of time. Thomas Zurbuchen, head of NASA’s science objective directorate, apologized for the late notification.
” I’m sure you were preparing something else tonight,” Zurbuchen said. “I question though that it would be more interesting than what we’re going to speak about here.”
The next action for OSIRIS-REx will be to place the tasting mechanism inside a return capsule installed on the spacecraft. The 31- inch (0.8-meter) size sample return pill is created to secure the asteroid sample throughout re-entry into Earth’s environment Sept. 24, 2023.
” We all have one goal, and that is to bring the maximum sample back to Earth,” Zurbuchen stated.
” We do not believe that there is anything we can do with the system that we have to go fix the diaphragm,” Zurbuchen stated. “So the variables that we can manage are: No. 1, how much we rattle this thing around, so we’ve decreased that with the actions that we’ve taken currently, and No. 2, is to reduce the time to get this stowed, at which point the particles are locked into the capsule that will bring them back to Earth.”
Over the weekend, engineers at Lockheed Martin’s control facility near Denver will validate the stow treatment, which did not initially account for the possibility that rock pieces and dust and particles might be leaking out of the sampling mechanism.
Zurbuchen stated NASA will also book time committed to OSIRIS-REx on the agency’s Deep Space Network, a group of big tracking and communication antennas at websites in California, Australia, and Spain. He said engineers at the space network will prioritize OSIRIS-REx’s “contingency operations” to guarantee the mission gets continuous communications coverage as ground teams command the delicate sample stow procedure.
On Monday, spacecraft operators near Denver will check out a camera taking a look at OSIRIS-REx’s sample return pill to keep an eye on the stow operation. If all goes according to plan, objective control might begin positioning the asteroid specimens inside the return provider as quickly as Tuesday, Lauretta stated.
” data-lazy-type=”iframe” src=”data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7″>< img alt ="" data-lazy-src ="” data-lazy-type =” iframe” src =” data: image/gif; base64, R0lGODlhAQABAIAAAAAAAP/// yH5BAEAAAAALAAAAAABAAEAAAIBRAA7″ >
The ground team will uplink commands for OSIRIS-REx to stow its sample in a series of steps, allowing engineers to regularly pause and evaluate the situation. Lauretta said the movement involved with the stow operation will likely trigger more particles to leakage out of the sampling system, and supervisors want to ensure the material doesn’t hinder any mechanical interfaces or damage the return pill.
It will all play out more than 200 million miles (320 million kilometers) from Earth, with a communications delay of more than 18 minutes.
” We can command the arm to move … obtain an image, download that image, evaluate it, and then make a decision,” Lauretta said.
Authorities hope the specimens could securely be sealed inside the sample return pill by the end of next week.
After the opening the sample return carrier’s cover, ground teams will send commands for the robotic arm to position the TAGSAM head onto a capture ring inside the capsule. Then it will activate a “tube cutter” to cut lines leading from the gadget’s nitrogen gas bottles, and fire a separation bolt to sever the TAGSAM head from the robotic arm.
” So that is a one-way ticket, and after that we move the arm away and the entire head remains inside that capture ring mechanism,” Lauretta. “And after that we’ll pull the sample return pill (cover) down. There are several locks. Just one latch is needed for Earth entry.”
Lauretta said he is confident the sample return pill can seal itself in spite of the threat of obstructions from floating asteroid particles.
” When the sample head is safely stowed in the return pill, it’s closed, it’s protected, and there will no more mass loss,” he stated.
The images of the overflowing tasting mechanism Thursday likewise prompted authorities to cancel a thruster shooting Friday to slow OSIRIS-REx’s speed away from Bennu. The burn would have preserved the option for a 2nd touch and go sampling perform at Bennu.
” We will not be returning to the asteroid,” Lauretta said. “So we said our goodbye, I believe, to Bennu on Tuesday, and we’re solely concentrated on stowing the sample securely, and after that once that’s done, on getting ready for return cruise and Earth return.”
With the decision to skip the sample mass measurement, researchers won’t understand precisely how much of Bennu they got until OSIRIS-REx brings the samples back to Earth.
” We were anticipating the sample mass measurement and the certainty that gave us in regards to planning the sample analysis activities,” Lauretta said. “But the bright side is we see a great deal of product.”
OSIRIS-REx will depart the area of Bennu in early March to begin the journey back to Earth. The spacecraft will launch the sample return pill as it approaches Earth, targeting a parachute-assisted landing at the Utah Test and Training Range while the OSIRIS-REx mothership diverts and heads once again into the planetary system.
Scientists will recuperate the capsule and transport it to NASA’s Johnson Space Center in Houston, where they will begin analysis of the Bennu specimens inside a beautiful astromaterials laboratory, the exact same center that houses lunar rocks returned by the Apollo astronauts.
OSIRIS-REx will bring home the most significant haul of asteroid product ever, but it’s not the only mission with sights on returning samples from an asteroid.
Japan’s Hayabusa 2 spacecraft is on course to release a sample carrier to land in Australia on Dec. 6 with a much smaller sized load of asteroid material than OSIRIS-REx.
NASA and the Japan Aerospace Expedition Company have accepted share a little percentage of the OSIRIS-REx and Hayabusa 2 samples in between U.S. and Japanese researchers.
While the objective’s scientific payoff won’t come for another three years, the OSIRIS-REx group is already digging into new data about the surface residential or commercial properties of Bennu. Scientists believe the within the asteroid is porous, and the stones on its surface are low-strength and easily crushable.
An initial evaluation of the spacecraft’s movement throughout the touch and go landing Tuesday suggests OSIRIS-REx’s sampling arm pushed about 2 inches, or 5 centimeters, into the loose dust on Bennu’s surface before shooting its nitrogen gas bottle.
” The contact was picked up by the accelerometers on-board the spacecraft,” Lauretta stated.
A pogo spring on the robotic arm “did not deflect visibly at all,” Lauretta stated, and the sampling mechanism continued moving into the asteroid’s gravelly surface, reaching a depth of approximately 19 inches, or 48 centimeters, before OSIRIS-REx triggered its back-away thrusters to remove again.
Then it took another 3 seconds for the spacecraft’s rocket thrusters put OSIRIS-REx in reverse.
” It took the thrusters an extra three seconds to stop that forward motion, and then start speeding up backwards, ultimately achieving that 40 centimeter per 2nd (0.9 miles per hour) escape velocity,” Lauretta said. “So that’s a wealth of information that will be supplied. It informs us a massive amount about the material residential or commercial properties of the regolith at the contact point.”
Evaluating of the OSIRIS-REx sampling system prior to launch revealed that the gadget was able to scoop up the most rocks and dust when it was able to burrow itself into asteroid-like material.
” I keep in mind early on in development, it was a real question,” Lauretta stated. “The mechanical properties of the surface area of the asteroid was most likely the largest unidentified in the mission style. So we had to create, everything from an entirely stiff surface like encountering a slab of concrete down to what we called the ‘fairy castle’ structure with nearly no resistance.
” And that was part of the challenge of the mission was coming up with a style that would operate under all of those various scenarios, maintaining spacecraft security primarily.
Email the author.
Follow Stephen Clark on Twitter: @StephenClark1