NASA’s OSIRIS-REx Probe Successfully Stows Space-Rock Sample

NASA’s pioneering OSIRIS-REx probe has bagged up its precious asteroid sample for return to Earth.

OSIRIS-REx has finished stowing the bits of the carbon-rich asteroid Bennu that it snagged last Tuesday (Oct. 20), successfully locking the material into the spacecraft’s return capsule, mission team members announced Thursday (Oct. 29).

And the sample appears to be substantial—far heftier than the 2.1 ounces (60 grams) the mission had set as a target, team members said. Indeed, OSIRIS-REx collected so much material on Oct. 20 that its sampling head couldn’t close properly; the head’s sealing mylar flap was wedged open in places by protruding Bennu pebbles.

The OSIRIS-REx team noticed that issue last week when examining photos of the head and its collected sample; flakes of escaped asteroid material drifted through the frames. To minimize the amount lost, the team decided to expedite the precise and complex stowing procedure, which was supposed to happen next week.

So, over the course of 36 hours on Tuesday and Wednesday (Oct. 27 and Oct. 28), engineers directed OSIRIS-REx to deposit the sampling head, which sat at the end of the probe’s robotic arm, into the return capsule; tug on the head to make sure it was secured properly; sever connections with the robotic arm; and lock up the return capsule via the locking of two latches.

This was all done while OSIRIS-REx was about 205 million miles (330 million kilometers) from Earth, meaning it took 18.5 minutes for each command to reach OSIRIS-REx, and another 18.5 minutes for each update from the probe to come back down to Earth. 

“We wanted to only attempt stow one time, and we wanted to make sure we were successful,” OSIRIS-REx mission operations manager Sandra Freund, of Lockheed Martin Space in Littleton, Colorado, said during a NASA news conference Thursday. “And we definitely were.”

The change of plans required a last-minute reallocation of time on NASA’s Deep Space Network (DSN), the system of radio telescopes that the agency uses to communicate with its far-flung probes. Because the stow operation was so important and so involved, OSIRIS-REx needed a large block of continuous DSN time, which other NASA missions sacrificed for the greater good.

It’s unclear exactly how much asteroid material now sits in OSIRIS-REx’s return capsule, which will come down to Earth in September 2023. The team canceled a planned post-sampling weighing procedure that would have involved spinning the probe, because this maneuver would have resulted in more sample loss. (Moving the arm—to photograph the sample and conduct the stow operation, for example—imparted grain-liberating acceleration, mission team members explained. So they wanted to minimize such motions.) 

But there’s definitely a lot of asteroid material on board, said mission principal investigator Dante Lauretta of the University of Arizona.

The sampling operation on Oct. 20 went extremely well, Lauretta said, and the head penetrated deep into Bennu’s surface—perhaps 19 inches (48 centimeters) or more. The team is confident that OSIRIS-REx pretty much filled its sampling head that day, meaning it likely backed

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OSIRIS-REx successfully stows sample of asteroid Bennu

OSIRIS-REx successfully stows sample of asteroid Bennu
Taken on Oct. 28 by NASA’s OSIRIS-REx spacecraft, this image shows the collector head after it was separated from the Touch-And-Go Sample Acquisition Mechanism arm. The collector head is secured onto the capture ring in the Sample Return Capsule. Credit: NASA/Goddard/University of Arizona/Lockheed Martin

NASA’s University of Arizona-led OSIRIS-REx mission has successfully stowed the spacecraft’s Sample Return Capsule and its abundant sample of asteroid Bennu. On Oct. 28, the mission team sent commands to the spacecraft, instructing it to close the capsule—marking the end of one of the most challenging phases of the mission.


“I’m very thankful that our team worked so hard to get this sample stowed as quickly as they did,” said Dante Lauretta, OSIRIS-REx principal investigator and a professor planetary sciences at the University of Arizona. “Now, we can look forward to receiving the sample here on Earth and opening up that capsule.”

“This achievement by OSIRIS-REx on behalf of NASA and the world has lifted our vision to the higher things we can achieve together, as teams and nations,” said NASA Administrator Jim Bridenstine. “Together, a team comprising industry, academia and international partners, and a talented and diverse team of NASA employees with all types of expertise, has put us on course to vastly increase our collection on Earth of samples from space. Samples like this are going to transform what we know about our universe and ourselves, which is at the base of all NASA’s endeavors.”

The mission team spent two days working around the clock to carry out the stowage procedure, with preparations for the stowage event beginning Oct. 24. The process to stow the sample is unique compared to other spacecraft operations and required the team’s continuous oversight and input over the two-day period. For the spacecraft to proceed with each step in the stowage sequence, the team had to assess images and telemetry from the previous step to confirm the operation was successful and the spacecraft was ready to continue. Given that OSIRIS-REx is currently more than 205 million miles from Earth, this required the team to also work with a greater than 18.5-minute time delay for signals traveling in each direction.

Throughout the process, the OSIRIS-REx team continually assessed the Touch-And-Go Sample Acquisition Mechanism’s wrist alignment to ensure the collector head was being placed properly into the Sample Return Capsule. Additionally, the team inspected images to observe any material escaping from the collector head to confirm that no particles would hinder the stowage process. StowCam images of the stowage sequence show that a few particles escaped during the stowage procedure, but the team is confident that a plentiful amount of material remains inside of the head.

“Given the complexity of the process to place the sample collector head onto the capture ring, we expected that it would take a few attempts to get it in the perfect position,” said Rich Burns, OSIRIS-REx project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Fortunately, the head was captured on the first

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Bennu asteroid samples tucked into Osiris-Rex spacecraft capsule

After the spacecraft Osiris-Rex lost some of its precious cargo from asteroid Bennu, the sample are now tucked away for the long journey home.

CAPE CANAVERAL, Fla — A NASA spacecraft tucked more than 2 pounds of asteroid samples into a capsule for return to Earth after losing some of its precious loot because of a jammed lid, scientists said Thursday.

They won’t know the precise amount of the cosmic haul from asteroid Bennu, more than 200 million miles (322 million kilometers) away, until the capsule parachutes into the Utah desert in 2023.

“We’ve still got a lot of work to do” to get the samples back safely, said lead scientist Dante Lauretta of the University of Arizona.

The spacecraft Osiris-Rex won’t depart Bennu’s neighborhood until March at the earliest, when the asteroid and Earth are properly aligned.

Osiris-Rex collected so much material from Bennu’s rough surface on Oct. 20 that rocks got wedged in the rim of the container and jammed it open. Some of the samples were seen escaping into space, so flight controllers moved up the crucial stowing operation.

RELATED: Asteroid samples escaping from jammed NASA spacecraft

RELATED: Video shows NASA probe touching asteroid, kicking up rubble

Based on images, scientists believe Osiris-Rex grabbed 4 1/2 pounds (2 kilograms) of rubble, a full load. The minimum requirement had been 2 ounces (60 grams) — a handful or two.

“Just imagine a sack of flour at the grocery store,” Lauretta said of the initial haul.

But tens of grams of material were lost following the successful touch-and-go maneuver and again this week when the spacecraft’s robot arm moved to put the samples inside the capsule.

“Even though my heart breaks for the loss of sample, it turned out to be a pretty cool science experiment and we’re learning a lot,” Lauretta told reporters.

While collecting the samples, the container on the end of the robot arm pressed down 9 to 19 inches (24 to 48 centimeters) during the six seconds of contact, indicating a sandy and flaky interior beneath the rough surface, Lauretta said.

The slow, tedious stowing operation took 36 hours. After each successful step, flight controllers cheered, saving the biggest and loudest response when the lid on the capsule finally was closed and latched, sealing the samples inside.

It will be September 2023 — seven years after Osiris-Rex rocketed from Cape Canaveral — before the samples arrive here.

Rich in carbon, the solar-orbiting Bennu is believed to hold the preserved building blocks of the solar system. Scientists said the remnants can help explain how our solar system’s planets formed billions of years ago and how life on Earth came to be. The samples also can help improve our odds, they said, if a doomsday rock heads our way.

Bennu — a black, roundish rock bigger than New York’s Empire State Building — could come dangerously close to Earth late in the next decade. The odds of a strike are 1-in-2,700. The good news is that while

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NASA’s OSIRIS-REx Successfully Stows Sample of Asteroid Bennu

The left image shows the OSIRIS-REx collector head hovering over the Sample Return Capsule (SRC) after the Touch-And-Go Sample Acquisition Mechanism arm moved it into the proper position for capture, recently. The right image shows the collector head secured onto the capture ring in the SRC. Both photos, released by NASA on October 29, 2020, were captured by the StowCam camera. The OSIRIS-REx team will now focus on preparing the spacecraft for the next phase of the mission – Earth Return Cruise. The departure window opens in March 2021 for OSIRIS-REx to begin its voyage home, and the spacecraft is targeting the delivery of the SRC to Earth on September 24, 2023. UPI

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NASA’s Osiris-Rex asteroid-blasting spacecraft stored 2 pounds of rock

NASA’s Osiris-Rex spacecraft successfully scooped up rocky space dust from the asteroid Bennu on Friday. But in a sense, it completed its task too well: Scientists quickly realized that the spacecraft’s sample-collecting arm had gathered so much material that its valves wouldn’t close. That was leading the dust to leak back into space.

“Time is of the essence,” Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA, said.

So this week, the mission team instructed Osiris-Rex to store its sample inside the designated return capsule ahead of schedule. On Thursday, NASA confirmed that the spacecraft had successfully done so. 

“I am extremely happy with the sample that we’ve collected,” Dante Lauretta, the Osiris-Rex mission lead, said in a briefing on Thursday. Scientists are pretty sure the spacecraft stashed at least 2 pounds (1 kilogram) of asteroid dust, also called regolith, he added.

That’s far more than the mission’s minimum goal of 2.1 ounces, which is about the mass of a small bag of potato chips. The leaking that occurred before the sample was stored away was only a matter of “tens of grams,” according to Lauretta.

Once Osiris-Rex returns to Earth in 2023, it’s set to drop the capsule holding the asteroid material into the atmosphere. Then the capsule should parachute down into the Utah desert for NASA to pick up. It will be the agency’s first sample collected from an asteroid.

Maneuvering a spacecraft 200 million miles away

osiris rex gif particles falling out

This series of three images, taken October 22, 2020, showed that the sampler head on NASA’s Osiris-Rex spacecraft was full of rocks and dust collected from asteroid Bennu. Some of these particles were slowly escaping.

NASA


To collect its asteroid sample, Osiris-Rex had to fly through a dangerous rock field and give Bennu a kind of cosmic high-five — it touched the surface for just six seconds.

The day after that brief landing, the spacecraft beamed images of its precious cargo back to NASA, but the scientists saw debris drifting away. The mission team had previously planned to spend a couple weeks assessing the sample, but they feared losing too much material to the vacuum of space. So they rushed the storage process, working day and night for two days to ensure the sample-collection arm could properly secure the sample inside the capsule.

The arm’s wrist had to align properly with the capsule so they’d fit together, which sounds simple, but because the spacecraft is 200 million miles away, every command and response faced an 18-minute lag.

By Tuesday, the probe’s arm had successfully placed its leaky sample-collecting head into the open capsule. To make sure it was locked in, the team directed the arm to tug on the collector head once more and make sure it was securely fastened.

By the following day, the team had detached the sample-collecting head from its arm and sealed the return capsule shut.

‘The more the merrier’ when it comes to sample material

asteroid bennu rotating osiris rex

A rotating mosaic of asteroid Bennu, composed of images

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NASA’s OSIRIS-REx probe successfully stores small sample of asteroid rocks in its belly

NASA’s OSIRIS-REx spacecraft has successfully stored a small cache of rocks that it grabbed from the surface of an asteroid named Bennu last week, sealing the pebbles inside the vehicle’s belly. The asteroid particles will now remain inside the spacecraft over the next three years, as OSIRIS-REx makes its way back to Earth.

OSIRIS-REx grabbed the sample on October 20th of last week, more than four years after launching from Earth on its mission to touch an asteroid. Using a thin robotic arm, the vehicle lightly tapped the asteroid Bennu, stirring up rocks on the surface and pushing some of the pebbles up into the spacecraft.

While the maneuver worked as planned, OSIRIS-REx was a little too good at this sample grab. The vehicle wound up collecting a substantial chunk of asteroid rocks, some of which were fairly large in size. These beefier pebbles then jammed a flap at the end of the arm that was supposed to keep the material enclosed inside. With the flap stuck open, some of the asteroid particles started escaping out into space. Images of the sample collector showed tiny particles dancing and swirling as they headed out into the void.

That discovery completely upended the mission team’s plans, as they raced to store the sample before more rocks floated out into space. Originally, the team had hoped to use this week to spin up the OSIRIS-REx spacecraft, measuring the vehicle’s momentum to find out just how much sample it had collected. But the engineers opted to cancel that, as the twirling could cause more rocks to escape. Instead, they decided to cut straight to storing the sample inside the main body of the spacecraft.

The storage process took a couple of days to complete, with the OSIRIS-REx team monitoring each maneuver the vehicle made and analyzing images taken by the spacecraft. Overall, it seems to have gone off just fine, and the collector is now properly secured inside of OSIRIS-REx. “We’re here to announce today that we’ve successfully completed that operation,” Rich Burns, the OSIRIS-REx project manager at NASA’s Goddard Space Flight Center, said during a press conference.

Unfortunately, the team doesn’t know for sure exactly how much material they stored since they had to cancel the spin maneuver. But they’re very confident that they grabbed more than what they hoped to grab. The OSIRIS-REx mission set a goal of snagging at least 60 grams of asteroid material from Bennu. Based on images taken of the robotic arm and the collector, the team members are confident they’ve grabbed at least 400 grams of material — if not more. The pictures only show about 17 percent of what’s inside the sample collector, according to Dante Lauretta, the principal investigator of the OSIRIS-REx mission at the University of Arizona. They estimate there are 400 grams in just that 17 percent of space alone, which means it’s possible the spacecraft has more than a kilogram in its

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NASA’s OSIRIS-REx secures asteroid sample after surprise leak

After a series of high-stakes maneuvers performed more than 200 million miles from Earth, NASA’s OSIRIS-REx spacecraft has successfully stowed its precious samples of the asteroid Bennu. The move follows a surprise leak first announced on October 23, as some of the spacecraft’s pristine space rocks slipped out of a jammed sampling mechanism and floated away into the void. The safeguarding of the sample ensures that the material—rocks and dust from the solar system’s origins—will safely make its way to Earth.



a close up of a clock: On October 22, two days after touching Bennu, engineers realized that OSIRIS-REx's Touch-and-Go Sample Acquisition Mechanism (TAGSAM) sampling head on was leaking precious rocks and dust. The culprit: a mylar flap designed to keep the material in the head, wedged open by larger rocks.


© Photograph by NASA/Goddard/University of Arizona

On October 22, two days after touching Bennu, engineers realized that OSIRIS-REx’s Touch-and-Go Sample Acquisition Mechanism (TAGSAM) sampling head on was leaking precious rocks and dust. The culprit: a mylar flap designed to keep the material in the head, wedged open by larger rocks.




With the door open, a technician at Kennedy Space Center inspects the inside of the sample return capsule, circular object at right, in 2016 during testing of the door. The leaking sampling head was placed inside this capsule for its journey back to Earth.


© Photograph by Kim Shiflett, NASA

With the door open, a technician at Kennedy Space Center inspects the inside of the sample return capsule, circular object at right, in 2016 during testing of the door. The leaking sampling head was placed inside this capsule for its journey back to Earth.


The sample was secured after a tense few days following OSIRIS-REx’s October 20 touchdown on Bennu, which made the spacecraft only the third—and NASA’s first—to collect a sample from an asteroid. But OSIRIS-REx did almost too good of a job: It picked up pieces of the asteroid large enough to wedge the sample-collection device partially open.

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As soon as the team noticed the debris leak on October 22, OSIRIS-REx personnel canceled several planned maneuvers and tests to minimize any disturbances to the sample-collection device, called TAGSAM (Touch-And-Go Sample Acquisition Mechanism). To protect the material in the device, which will be returned to Earth in 2023, OSIRIS-REx’s controllers quickly acted to tuck the sample into a sealed capsule—a maneuver that was completed on October 28.

The successful stowing process comes as a welcome relief, as OSIRIS-REx’s cache of primordial dirt and rocks could shed light on how the planets—and maybe even life on Earth—came to be. By studying the ingredients that were present in the newborn solar system, scientists hope to unravel the 4.5 billion-year process that produced Earth and everything on it.

Just hours into the effort to safeguard the sample, OSIRIS-REx principal investigator Dante Lauretta acknowledged that the accelerated maneuver came with its own risks, but he stressed that quickly locking down the sample was the most prudent course of action.

“Once it’s in the return capsule, it’s all contained, and anything inside there is coming back to the surface of Earth,” he said on October 27.

The jammed sampling mechanism was the latest surprise thrown at OSIRIS-REx by Bennu, a world shaped like a top and not much wider than the Empire State Building. Bennu’s extremely weak gravity and treacherous, boulder-covered surface pushed the spacecraft and its team to their limits. To descend to the asteroid’s surface, the spacecraft needed to switch to backup navigation software mid-mission, and engineers had to model even the slightest

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NASA to launch delicate stowing of Osiris-Rex asteroid samples

NASA’s robotic spacecraft Osiris-Rex is set to begin on Tuesday a delicate operation to store the precious particles it scooped up from the asteroid Bennu, but which were leaking into space when a flap got wedged open.

The probe is on a mission to collect fragments that scientists hope will help unravel the origins of our solar system, but that hit a snag after it picked up too big of a sample.

Fragments from the asteroid’s surface are in a collector at the end of the probe’s three-meter (10-foot) arm, slowly escaping into space because some rocks have prevented the compartment closing completely.

That arm is what came into contact with Bennu for a few seconds last Tuesday in the culmination of a mission launched from Earth some four years ago. 

The probe is thought to have collected some 400 grams (14 ounces) of fragments, far more than the minimum of 60 grams needed, NASA said previously.

Scientists need to stow the sample in a capsule that is at the probe’s center, and the operation was moved up to Tuesday from the planned November 2 date due to the leak.

“The abundance of material we collected from Bennu made it possible to expedite our decision to stow,” said Dante Lauretta, project chief.

Osiris-Rex is set to come home in September 2023, hopefully with the largest sample returned from space since the Apollo era.

The stowing operation will take several days, NASA said, because it requires the team’s oversight and input unlike some of Osiris-Rex’s other operations that run autonomously.

After each step in the process the spacecraft will send information and images back to Earth so scientists can make sure everything is proceeding correctly.

The probe is so far away that it takes 18.5 minutes for its transmissions to reach Earth, and any signal from the control room requires the same amount of time to reach Osiris-Rex.

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NASA’s OSIRIS-REx Spacecraft Goes for Early Stow of Asteroid Sample

NASA’s OSIRIS-REx Spacecraft Goes for Early Stow of Asteroid Sample

PR Newswire

WASHINGTON, Oct. 26, 2020

WASHINGTON, Oct. 26, 2020 /PRNewswire/ — NASA’s OSIRIS-REx mission is ready to perform an early stow on Tuesday, Oct. 27, of the large sample it collected last week from the surface of the asteroid Bennu to protect and return as much of the sample as possible.

This illustration shows NASA’s OSIRIS-REx spacecraft stowing the sample it collected from asteroid Bennu on Oct. 20, 2020. The spacecraft will use its Touch-And-Go Sample Acquisition Mechanism (TAGSAM) arm to place the TAGSAM collector head into the Sample Return Capsule (SRC).
This illustration shows NASA’s OSIRIS-REx spacecraft stowing the sample it collected from asteroid Bennu on Oct. 20, 2020. The spacecraft will use its Touch-And-Go Sample Acquisition Mechanism (TAGSAM) arm to place the TAGSAM collector head into the Sample Return Capsule (SRC).

On Oct. 22, the OSIRIS-REx mission team received images that showed the spacecraft’s collector head overflowing with material collected from Bennu’s surface – well over the two-ounce (60-gram) mission requirement – and that some of these particles appeared to be slowly escaping from the collection head, called the Touch-And-Go Sample Acquisition Mechanism (TAGSAM).

A mylar flap on the TAGSAM allows material to easily enter the collector head, and should seal shut once the particles pass through. However, larger rocks that didn’t fully pass through the flap into the TAGSAM appear to have wedged this flap open, allowing bits of the sample to leak out.

Because the first sample collection event was so successful, NASA’s Science Mission Directorate has given the mission team the go-ahead to expedite sample stowage, originally scheduled for Nov. 2, in the spacecraft’s Sample Return Capsule (SRC) to minimize further sample loss.

“The abundance of material we collected from Bennu made it possible to expedite our decision to stow,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. “The team is now working around the clock to accelerate the stowage timeline, so that we can protect as much of this material as possible for return to Earth.”

Unlike other spacecraft operations where OSIRIS-REx autonomously runs through an entire sequence, stowing the sample is done in stages and requires the team’s oversight and input. The team will send the preliminary commands to the spacecraft to start the stow sequence and, once OSIRIS-REx completes each step in sequence, the spacecraft sends telemetry and images back to the team on Earth and waits for the team’s confirmation to proceed with the next step.

Signals currently take just over 18.5 minutes to travel between Earth and the spacecraft one-way, so each step of the sequence factors in about 37 minutes of communications transit time. Throughout the process, the mission team will continually assess the TAGSAM’s wrist alignment to ensure the collector head is properly placed in the SRC. A new imaging sequence also has been added to the process to observe the material escaping from the collector head and verify that no particles hinder the stowage process. The mission anticipates the entire stowage process will take multiple days, at the end of which the sample will be safely sealed in the SRC for the spacecraft’s journey

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Bennu Asteroid Particles Leaking From NASA’s OSIRIS-REx Spacecraft

KEY POINTS

  • About 5 to 10 grams of Bennu’s surface particle samples are diffusing out in space
  • Particles escape slowly from flaps of the spacecraft’s Touch-And-Go Sample Acquisition Mechanism
  • The mission team remains positive to bring home abundant samples for future studies 

NASA’s OSIRIS-REx team’s mission to collect samples from asteroid Bennu was successful so much so that particles are diffusing out from the spacecraft. The mission team was tasked to collect at least 2 ounces or 60 grams of the Bennu’s surface material. 

Upon review of the images they obtained as they performed the collection, the team noticed that the sample collector head of the  OSIRIS-REx appeared to be full. However, the images reveal that the particles are somewhat escaping slowly from the part of the spacecraft called the Touch-And-Go Sample Acquisition Mechanism or TAGSAM.

The team suspected that they collected abundant sample particles from Bennu that excess materials are escaping through small flaps of the TAGSAM’s lid. Larger rock particles may have wedged open the lid, the team said. 

This NASA frame grab from a gif series captured by Osiris-Rex's camera on October 22, 2020 shows the sampler head on the spacecraft full of rocks and dust collected from the surface of the asteroid Bennu This NASA frame grab from a gif series captured by Osiris-Rex’s camera on October 22, 2020 shows the sampler head on the spacecraft full of rocks and dust collected from the surface of the asteroid Bennu Photo: NASA / Handout

“We are working to keep up with our own success here, and my job is to safely return as large a sample of Bennu as possible,” Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona in Tucson, said in a press release. Lauretta leads the mission and is tasked with the mission’s data processing. 

“The loss of mass is of concern to me, so I’m strongly encouraging the team to stow this precious sample as quickly as possible,” Lauretta added. 

By estimates, the team is losing between 5 to 10 grams of Bennu’s surface particle samples. The problem is that they won’t know the actual amount of what they collected until NASA’s OSIRIS-REx lands back home in 2023.  

Lauretta explained that they don’t have the capability to close the flaps through which the particles are escaping. At the same time, the team isn’t sure as well how big are the rocks that keep the flaps open.  There is also no way of knowing what sizes of particles can escape through the opened flaps. 

According to CNN, the problem with particles escaping the TAGSAM was not anticipated during the mission’s dry-runs. And, although trials include having large rocks during the collection, the team didn’t calculate the depth through which they should thrust the collector head into Bennu.

Nevertheless, the team remains optimistic about the samples they have.   They believe they can bring home enough samples for future studies. 

“Although we may have to move more quickly to stow the sample, it’s not a bad problem to have. We are so excited to see what appears to be an abundant sample that will inspire science for decades beyond this historic moment,” Lauretta said as quoted by CNN. 

Scientists celebrate as NASA's robotic spacecraft Osiris-Rex briefly touches down on asteroid Bennu to collect samples. "The spacecraft did everything it was supposed to do," says Dante Lauretta from University of Arizona. Scientists celebrate as

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