On July 18-20, the team behind NASA’s OSIRIS-REx mission rehearsed recovering a mock sample return capsule from the location where the real one, with fragments of asteroid Bennu, will land on Sept. 24: the Utah desert.
Though the team has rehearsed portions of the recovery operation many times this year, this was the most realistic rehearsal yet, taking place at the Department of Defense’s Utah Test and Training Range about 80 miles (130 kilometers) southwest of Salt Lake City. Besides taking place at the real landing location, the rehearsal included helicopter training for the OSIRIS-REx team members who will fly by helicopter to retrieve the sample capsule from its landing site inside a 36-mile by 8.5-mile (58-kilometer by 14-kilometer) ellipse on the military range.
Here are a few highlights from the rehearsal:
OSIRIS-REx team members practice collecting soil samples on the Department of Defense’s Utah Test and Training Range. On July 18-20, 2023, the team rehearsed retrieving a mock sample capsule at the location where the real one, with samples of asteroid Bennu, will land on Sept. 24. NASA’s OSIRIS-REx spacecraft collected a sample from Bennu in October 2020 and has been traveling back to Earth with it since May 2021. This picture was taken on Tuesday, July 18. Credit: NASA/Keegan Barber.OSIRIS-REx team members practice getting a mock sample capsule packed for its helicopter flight to a clean room on the Department of Defense’s Utah Test and Training Range. On July 18-20, 2023, the team rehearsed retrieving a mock sample capsule at the location where the real one, with samples of asteroid Bennu, will land on Sept. 24. NASA’s OSIRIS-REx spacecraft collected a sample from Bennu in October 2020 and has been traveling back to Earth with it since May 2021. This picture was taken on Wednesday, July 19. Credit: NASA/Keegan Barber.A military representative checks the mock sample capsule’s landing site for unexploded ordnance. He will be the first person to approach the real capsule, with samples of asteroid Bennu, when it lands at the at the Department of Defense’s Utah Test and Training Range on Sept. 24. This picture was taken on Tuesday, July 18, at the OSIRIS-REx team’s rehearsal in Utah, which took place July 18-20, 2023. NASA’s OSIRIS-REx spacecraft collected a sample from Bennu in October 2020 and has been traveling back to Earth with it since May 2021. Credit: NASA/Keegan Barber.A helicopter practices transporting a mock sample capsule, packed for travel, at the Department of Defense’s Utah Test and Training Range. On July 18-20, 2023, the team rehearsed retrieving a mock sample capsule at the location where the real one, with samples of asteroid Bennu, will land on Sept. 24. NASA’s OSIRIS-REx spacecraft collected a sample from Bennu in October 2020 and has been traveling back to Earth with it since May 2021. This picture was taken on Wednesday, July 19. Credit: NASA/Keegan Barber.
The capsule looked like something from a 1960s sci-fi flick. Resting on the ground, slightly tilted, its white heat shield flaked off in places, it looked how one would expect after speeding in from outer space and streaking across the sky like a shooting star. Despite its appearance, the mini-fridge-sized object had, in fact, never left the surface of Earth.
OSIRIS-REx recovery team members from University of Arizona, Lockheed Martin and NASA’s Johnson Space Center approach the sample capsule during a field rehearsal in Colorado at Lockheed Martin Space in June 2023. Credit: Lockheed Martin Space
Instead, it was a replica of the sample capsule mounted on NASA’s OSIRIS-REx spacecraft, which has been cruising through space since it departed asteroid Bennu in May 2021 with an estimated half-pound of pristine asteroid material aboard. For training purposes, engineers placed the replica capsule on a field on the Lockheed Martin campus near Littleton, Colorado, where the spacecraft was built.
OSIRIS-REx team members from NASA, Lockheed Martin, and the University of Arizona had gathered in Littleton on June 27 and 28 to rehearse recovering the capsule. The real one will land on the Department of Defense’s Utah Test and Training Range on Sept. 24.
“We’re literally on a playground here,” said mission Principal Investigator Dante Lauretta, a professor of planetary sciences at University of Arizona in Tucson. “We have room to mess up and practice for the real thing.”
For the June exercise, the recovery team members took their positions next to wooden stakes that represented the four helicopters that will fly them to the capsule landing site.
Picking up a container that dropped from the sky via parachute, bearing 4.5-billion-year-old material collected from an asteroid, is a big deal. The Bennu sample contains primitive material, which could include organic compounds that are found in all Earth life. This material may provide insight into a time when the Sun and planets were born in the swirling cloud of gas and dust that became the solar system. A major goal of the OSIRIS-REx mission is to understand the evolution of organic molecules through solar system history.
Such pristine asteroid material is precious to researchers because it has been shielded from Earth’s environment, unlike meteorites that fall to the ground and are collected on the surface. So the team in Colorado practiced taking samples from the environment around the capsule to create a library of everything it could get exposed to – soil, air, organic matter and so on.
Documenting the environmental conditions around the capsule will be critical for science, Lauretta said: “That way, if we find something that looks fundamental to the origin of life, we’ll have no doubt, and should be able to rule it out as a contaminant because of that documented history.”
Before any team members could approach the capsule to collect environmental evidence, Vicki Thiem, a safety engineer with Lockheed Martin, rehearsed taking its temperature, which she’ll do on Sept. 24 to ensure the capsule has cooled down from its fiery descent through the atmosphere.
Next, the safety team practiced inspecting the area around the capsule for potential hazards, such as gases that might be emanating from it. Once the capsule was secured, Lauretta and his team inspected the terrain, planting little red flags into the ground to demarcate a “keep-out zone” where they needed to collect samples.
Team members from NASA’s OSIRIS-REx mission rehearse moving the sample capsule into a clean room at Lockheed Martin designed to closely resemble the one that will be used at the Department of Defense’s Utah Test and Training Range on Sept. 24, 2023. Credit: Lockheed Martin Space
Once the capsule was ready for transport, two people lifted the 100-pound (45-kilogram) replica into a metal crate and wrapped it in multiple sheets of a non-reactive plastic material and then a tarp. Next, they wrapped the crate in a harness that was secured to a cable that, in real life, will be attached to a helicopter and flown to a clean room set up in a hangar where the capsule will be opened and the sample canister extracted. The day after the sample lands on Earth, the canister and capsule will be flown to NASA’s Johnson Space Center in Houston where the sample will be cared for, stored, and distributed to global scientists.
The OSIRIS-REx team has two rehearsals left, each with increasingly realistic conditions, at the Utah military training range where the capsule will land this fall.
When NASA’s OSIRIS-REx spacecraft releases a capsule with material from asteroid Bennu onto the Utah desert on Sept. 24, it will become the latest in a line of missions to gather samples from space and deliver them to Earth. Collecting material from space is a challenging feat that requires teams of dedicated scientists and engineers, innovative technology, and patience. But the scientific breakthroughs these samples unlock make the effort worthwhile as we attempt to understand the origins of our planet and the life that thrives here.
The practice of retrieving samples from space began in 1969 with NASA’s Apollo 11 mission, the first to land astronauts on the Moon. Many more sample-gathering missions to the Moon and beyond followed, growing in ambition with each passing decade. Here is an overview of the history and future of missions, organized by NASA and its partners, to bring home pieces of space.
1969: NASA’s Moonwalk Delivers First Space Samples
This photograph, taken during the second Apollo 12 extravehicular activity, shows two NASA spacecraft on the surface of the Moon. The Apollo 12 Lunar Module is in the background. The uncrewed Surveyor 3 spacecraft is in the foreground. Credit: NASA
NASA astronaut Neil Armstrong’s famous line, “That’s one small step for [a] man, one giant leap for mankind,” commemorated humanity’s first footsteps on a world beyond Earth. It also launched a new era of science, engineering, and exploration. Apollo astronauts collected and returned 842 pounds (382 kilograms) of rocks and dust across six missions. Because Moon rocks are better preserved than Earth rocks, they offered unprecedented insight into how our planet and solar system formed – a history largely erased on Earth by erosion, climate cycles, volcanic activity, and plate tectonics. Among many other things, Apollo samples revealed that the makeup of the Moon and Earth are so similar the two likely formed from the same material. This finding led scientists to theorize that the Moon formed from rock and metal that flung off a collision between a young Earth and a Mars-size object about 4.5 billion years ago.
2004: Genesis Grabs Solar Wind
An artist’s rendering of solar wind, which is a stream of charged particles continually released from the Sun. Credit: NASA
NASA’s Genesis spacecraft delivered the first samples from beyond the orbit of the Moon in 2004. Placed for more than two years in a gravitationally stable point between the Earth and Sun, the spacecraft collected charged particles streaming out from the Sun, called the solar wind. Scientists wanted to study these particles because they are thought to reflect the chemical composition of the solar system when it was just forming nearly 4.6 billion years ago. After analyzing the sample scientists were surprised to see that Sun particles had different versions, or isotopes, of oxygen and nitrogen compared to Earth. They had expected the Sun and planets to have similar isotopic signatures since everything in the solar system formed from the same cloud of gas and dust, called the solar nebula. One reason for the difference may be that Earth and the rest of the rocky, inner planets formed from the dust of the nebula, whereas the Sun formed from both gas and dust.
2006: Collecting a Comet’s Dusty Halo
NASA’s Hubble Space Telescope captured this image of comet ISON, wrapped in a dusty halo, streaking through the sky in April 2013. Credit: NASA/ESA/Hubble Heritage Team
In 2006, NASA’s Stardust mission became the first to collect comet samples and deliver them to Earth. Like the name suggests, Stardust captured dust particles – 10,000 of them – from the halo of dust and gas, called a coma, surrounding comet Wild 2. Scientists made some key discoveries after analyzing bits of Wild 2. Among them was the first detection of glycine in a comet. Glycine is an amino acid, which is a fundamental building block of Earth life. Finding glycine in comet dust supported the theory that some of life’s ingredients formed in space and were delivered to Earth – and possibly other worlds – by comets and asteroids.
2010 & 2020: Going to the Source for History of Solar System
Asteroid Bennu, the target of NASA’s OSIRIS-REx mission, has some similarities with asteroid Ryugu, the target of JAXA’s Hayabusa2 mission — but the two asteroids have their differences, too. After OSIRIS-REx returns a sample of Bennu on Sept. 24, scientists will have a chance to compare and contrast the two asteroids in their labs. Credit: University of Arizona
Asteroid dust – older and better preserved than any material on Earth – offers scientists a window into the birth of the solar system. The first studies of asteroid samples were made possible by JAXA (the Japan Aerospace Exploration Agency), when its Hayabusa spacecraft returned in 2010 with thousands of particles from asteroid Itokawa. Hayabusa2 followed with 0.2 ounces, or 5.4 grams, of asteroid Ryugu in 2020, far exceeding mission requirements. Itokawa and Ryugu samples revealed the structure and chemical composition of “rubble pile” asteroids, which are made of rocks and boulders loosely held together by gravity. The samples also showed that some asteroids, as predicted, contain organic molecules, which could be some of the building blocks of all known life forms. Soon, scientists will have an opportunity to compare Itokawa and Ryugu samples to pieces of asteroid Bennu, which are on their way to Earth now aboard the OSIRIS-REx spacecraft. Through an international agreement, NASA and JAXA are collaborating to analyze and compare samples from the three asteroids, two of which — Ryugu and Bennu — may have broken off the same parent asteroid billions of years ago.
2023: Cruising Back to Earth with Bennu Rocks
Captured on Oct. 20, 2020, during the OSIRIS-REx mission’s Touch-And-Go sample collection event, this series of two images shows the SamCam imager’s field of view at the moment before and after the NASA spacecraft touched down on asteroid Bennu’s surface. Credit: NASA/Goddard/University of Arizona
Setting out to collect at least 2 ounces, or 60 grams, of dust and rocks from Bennu, OSIRIS-REx is on its way home with an estimated 8.8 ounces, or 250 grams, of material, which is just over a cupful. OSIRIS-REx collected the sample from Bennu on Oct. 20, 2020. After the sample reaches Earth on Sept. 24, generations of scientists will get to probe dust from Bennu in their labs to address dozens of questions about the nature of asteroids, the early solar system, and the origins of life. While at Bennu, the OSIRIS-REx spacecraft detected organic carbon and signs that the material Bennu is made of had interacted with liquid water in the past. When the samples reach Earth, scientists will be able to see the complete chemical makeup of Bennu and piece together the history of water and organic matter on the asteroid.
Future Missions
2029: Martian Moons Get the Spotlight
The High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter took this picture of the larger of Mars’ two moons, Phobos on March 23, 2008. This image was taken from a distance of about 4,200 miles (6,800 kilometers). It is presented in color by combining data from the camera’s blue-green, red, and near-infrared channels. Credit: NASA/JPL-Caltech/University of Arizona
JAXA will launch its MMX (Martian Moons eXploration) mission in 2024 to study the Martian moons Phobos and Deimos up close for the first time in history. MMX also will collect surface samples from Phobos, the farthest sampling location yet. JAXA will deliver the samples to Earth in 2029. This mission, which includes a NASA instrument, technology-demonstration sampling system and NASA-supported participating scientists from U.S. institutions, will help address questions about the evolution of Mars and the formation of its two moons.
2033: The Red Planet Comes to Earth
One of the big goals of space exploration is to determine whether Mars could have supported microbial life, or still does. Orbiters and rovers at the Red Planet have found intriguing evidence that early Mars had liquid water and a protective atmosphere, conditions that could have supported life as we know it. A portable lab in the belly of NASA’s Curiosity rover has even detected organic molecules in Martian soil that may – or may not – be related to life. To try to settle the question of Martian habitability, scientists have dreamt for decades of bringing Martian material to Earth to analyze it with cutting-edge technologies that are too big and too complex to send to space.
Their dreams could soon come true, as NASA and ESA (the European Space Agency) are designing a multi-mission campaign to retrieve samples that NASA’s Mars 2020 Perseverance rover is currently collecting from an ancient river delta in Jezero Crater. Called Mars Sample Return, the campaign is one of the most coordinated endeavors in spaceflight, involving multiple spacecraft, launches, and government agencies. The first spacecraft in a series needed to pick up Perseverance’s samples and bring them to Earth is scheduled to launch in 2027.
This week, NASA’s OSIRIS-REx science team is meeting as a whole for the last time before the sample of asteroid Bennu arrives on Earth. This occasion marks the last chance for the group to convene to make sure team members, lab facilities, and sample-analysis techniques are working as expected and ready for the delivery of Bennu’s rocks this September.
In the post below, Jason Dworkin, OSIRIS-REx project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, reflects on the big science questions that inspired this daring mission.
Jason Dworkin is an astrobiologist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the project scientist for NASA’s OSIRIS-REx mission. He is standing in NASA Goddard’s Astrobiology Analytical Laboratory, where he and other scientists study meteorites, Apollo Moon samples, plus comet and asteroid samples. Dworkin’s lab will receive pieces of asteroid Bennu for study after the sample arrives on Earth on Sept. 24, 2023. In this picture, Dworkin is holding a fragment of the Canyon Diablo meteorite, which struck Earth about 50,000 years ago, creating Meteor Crater in Arizona. Credit: Dennis Drenner.
There are only a few months left until NASA’s OSIRIS-REx delivers a sample of asteroid Bennu on Sept. 24, 2023. It’s feeling more and more real every day. I feel as though I have so much left to do, even though I’ve already spent 19 years preparing for this moment.
When the sample returns, 233 scientists globally, including me, will get to explore the asteroid in our labs. In doing so, we will address dozens of questions about asteroids, the early solar system, and the origins of life. You can see these questions reflected in the full name of the mission and spacecraft: Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer. (I’ll get deeper into the name later.)
I am an astrobiologist at NASA Goddard. I’m also the project scientist for OSIRIS-REx, which means I help manage mission science. My specialization is in the chemistry related to the origins of life, and so I work a lot with space rocks. My team in the Astrobiology Analytical Laboratory studies meteorites, Apollo Moon samples, comet samples from NASA’s Stardust mission, and asteroid samples (we’ve analyzed pieces of Itokawa and Ryugu, asteroids sampled by our partner, JAXA, or the Japanese Aerospace Agency). JAXA is among the many institutions that will get pieces of Bennu.
When our Goddard lab receives the first pieces of Bennu in October 2023, we will analyze them like a forensics lab, including grinding them into dust and subjecting them to boiling water, acid, and more. All this to gain insight into the chemistry of the compounds in the rocks.
This graphic shows a global map of destinations for the asteroid Bennu sample, which will arrive on Earth on Sept. 24, 2023. Below the map is a list of the institutions that will be the first to receive samples for a diversity of scientific investigations. The map is centered on Houston, where the sample will be curated and stored for the wider scientific community of today and of the future. Credit: NASA/Goddard/University of Arizona.
Besides my own work and that of my global colleagues, one of the most exciting things for me about the OSIRIS-REx mission is that ¾ of the Bennu sample will be put aside for the global scientific community and for the future. This practice is a legacy from the Apollo missions – we’re still opening and analyzing new caches of Moon rocks brought here by astronauts about 50 years ago! Saving extraterrestrial samples for the future ensures that they can be analyzed by scientists not yet born, using techniques not yet invented, to address questions that were unanswerable when the samples were collected.
We don’t know what questions future scientists will have about asteroids, but here are some of the biggest ones driving the science of this generation:
Does the sample contain organic compounds that could have influenced the origins of life?
This question relates to the Origins, “O,” part of the OSIRIS-REx acronym as it applies to NASA’s search for the origins of life on Earth and possibly elsewhere in the solar system and beyond. All Earth life has specific chemicals, such as amino acids and sugars. We know that asteroids contain the molecular precursors to these chemicals, and we suspect that asteroids may have delivered these precursors to Earth. With Bennu samples, we will analyze the properties of these precursor chemical compounds and try to map out if, and how, these chemicals could have evolved into life.
How does the Bennu sample compare with our interpretation of data collected at the asteroid?
This question is related to the Spectral Interpretation, “SI,” and Resource Identification, “RI,” parts of OSIRIS-REx. We will analyze the mineral and chemical makeup of the samples to see if it aligns with what we expected based on spectral, thermal, and physical data gathered by the spacecraft at the asteroid. Being able to test our interpretation of spacecraft data in this unprecedented way — by comparing data from space to pieces of the physical object — will help us improve future missions and interpretations of telescopic and spacecraft data.
What does the sample tell us about the history of the solar system?
This question relates to the rest of the Origins, “O,” and some of the Security, “S,” parts of OSIRIS-REx. Besides the origins of life, we are also interested in the origin of our solar system. Because we suspect that Bennu could be older than our solar system, we hope the sample will open a window into the earliest time of solar system formation. We are interested in learning more about the condensation of gas and dust that formed the Sun; the formation and destruction of Bennu’s parent asteroid (we think Bennu broke off a larger asteroid during a collision billions of years ago); the formation of Bennu and its migration to the inner solar system, where its orbit will continue inching closer to Earth’s over hundreds of years; and to the formation of the crater on Bennu’s surface where we collected our sample.
How has the sample changed since the spacecraft collected it?
The act of sample collection, the Regolith Explorer, “REx,” part of the mission name, was violent and may have influenced the chemistry of the pieces that are coming home, not to mention their three-year journey between Bennu and our laboratories. Thus, we will study the sample to understand what kinds of physical and chemical changes it experienced to ensure that we can draw accurate conclusions from our laboratory experiments.
ByRichard Witherspoon, OSIRIS-REx Ground Recovery Lead, Lockheed Martin
In anticipation of NASA’s OSIRIS-REx asteroid sample delivery this fall, the team held our first round of rehearsals April 17 to April 27. Our goal was to practice retrieving the spacecraft’s sample capsule from a simulated landing site at Lockheed Martin’s campus near Denver.
I am the Lockheed Martin-based ground recovery lead for sample recovery operations and will help guide the team through the real-life retrieval process when the capsule – carrying pristine material gathered from asteroid Bennu – lands on the Department of Defense’s Utah Test and Training Range in the Great Salt Lake Desert on Sept. 24.
A view from the Department of Defense’s Utah Test and Training Range, where NASA’s sample of asteroid Bennu will land on Sept. 24, 2023. The scene looks west from Wig Mountain towards the Nevada border and the desert basin where the sample capsule will land. Credit: NASA Goddard/Dan Gallagher
When the stakes for science are this high, it’s imperative we get it right. So, we practice! For almost two years, our team — which includes NASA, Lockheed, and University of Arizona — has been busy writing recovery procedures, thinking through every scenario that could happen to the sample capsule as it lands on Earth, and planning how to properly handle each scenario.
This first round of preparations marks a highly anticipated milestone for the OSIRIS-REx mission and our team. We have been planning the sample capsule recovery process for a very long time, and it’s exciting to see it all become real now, as we practice our procedures and work with hardware.
NASA’s Johnson Space Center curation team practices collecting environmental samples from the ground around the mock sample capsule, located in the bottom left corner, at Lockheed Martin’s campus near Denver. NASA team members pictured (left to right): Rachel Funk, Melissa Rodriguez, Curtis Calva, and Nicole Lunning. Credit: Lockheed Martin.
This was just the first of many upcoming rehearsals; six will take place before September. These are integral activities that teach us things like if a step in the recovery process is missing, or if we need to re-order a procedure, and more. Getting every step right is critical to preserving the pristine nature of the asteroid sample.
These trials also enable us to practice scenarios where everything goes according to plan, as well as ones where sample recovery goes differently than anticipated. This is also why additional rehearsals will be held in the coming months, with each one increasingly mirroring the real thing.
For example, in April, we hand-placed the sample capsule in the field in various positions and had the team practice recovering it. In July, we’ll release the capsule from the back of a truck at the Utah training range to better experience real-life recovery conditions. For the final dress rehearsal in August, we’ll drop the capsule from a helicopter onto a 10-mile (16-kilometer) by 9-mile (14-kilometer) area in Utah and time how long it takes the recovery team to find it and bring it back to the processing location. The faster the better.
At this point, I can really feel the energy starting to radiate across our recovery team, as we look forward to the big moment of return later this year!
The clean room team practices disassembling the sample capsule at Lockheed Martin. Team members pictured (clockwise): Mike Kaye (Lockheed Martin), Ryan Paquette (Lockheed Martin), Wayland Connelly (NASA), Nicole Lunning (NASA), and Levi Hanish (Lockheed Martin). Credit: Lockheed Martin.
Right now, we’re spending most of our time working with the curation team from NASA’s Johnson Space Center in Houston to validate communication processes upon retrieval of the asteroid sample in Utah. The curation team will process and store the sample at Johnson, where it will be delivered as soon as possible after landing. But first, as soon as the sample capsule lands in Utah, the curation team will gather dirt, water, and other remnants from around the capsule’s landing site to test and catalog the elements the capsule will have been exposed to. This will help the team discern which particles on the capsule came from Bennu and which were picked up from its Utah desert landing site.
It’s important that the entire team practices together and works things out ahead of time, so we can foster an environment of good situational awareness among everyone actively involved in the recovery.
Though there’s much work still to be done, I’m immensely proud of the meticulous planning and preparation the OSIRIS-REx team has already accomplished. Most all, I’m looking forward to all the ground-breaking knowledge this unique asteroid sample will provide scientists for generations to come.
This week, we have been recapping noteworthy OSIRIS-REx mission events each day so you can catch up on anything you may have missed so far on NASA’s first mission to collect a sample from an asteroid.
(Post #4 in a series of four)
At 1:50 p.m. EDT on Oct. 20, 2020, NASA’s OSIRIS-REx spacecraft fired its thrusters to nudge itself out of orbit around Bennu. It extended the shoulder, then elbow, then wrist of its 11-foot (3.35-meter) sampling arm and transited across Bennu while descending about half a mile (805 meters) toward the surface. After about a four-hour autonomous descent to a 26-foot- (8-meter-) wide spot on Bennu, past menacing boulders that could tip the spacecraft or the sample head and thwart the sample grab, OSIRIS-REx contacted the surface. It then fired a burst of nitrogen gas that stirred up dust and rocks, which were captured by the sample-collection head. Finally, OSIRIS-REx fired its thrusters and safely backed away from Bennu, allowing a captivated global audience to breathe a collective sigh of relief.
Before departing Bennu, OSIRIS-REx conducted one last flyby of the sample site, “Nightingale,” so scientists could see how the spacecraft’s contact with Bennu’s surface altered the site. They saw something astonishing: Even though the spacecraft barely touched the surface, it left a sizeable crater and scattered many rocks. Scientists ran hundreds of computer simulations to understand how this could have happened, given they had expected the spacecraft to leave only a small divot in the surface.
That’s when they learned that the particles making up Bennu’s exterior are loosely packed and lightly bound to each other, which means they act more like a fluid than a solid. Had it not fired its thrusters to back away immediately after grabbing a sample, OSIRIS-REx would have sunk into Bennu.
On May 10, 2021, the spacecraft departed Bennu and headed back toward Earth to drop off the sample-return capsule. When it arrives here on Sept. 24, 2023, OSIRIS-REx will release its sample capsule to land on Earth in the Utah desert, but the spacecraft will not land itself. With the sample delivered, the spacecraft will set off on a new mission, OSIRIS-APEX (OSIRIS-Apophis Explorer), to explore asteroid Apophis.
This week, we are recapping noteworthy OSIRIS-REx mission events each day so you can catch up on anything you may have missed so far in NASA’s first mission to collect a sample from an asteroid.
(Post #3 in a series of four)
Pictured here are the four candidate sample collection sites on asteroid Bennu selected by NASA’s OSIRIS-REx mission. Site Nightingale (top left) is located on Bennu’s northern hemisphere. Sites Kingfisher (top right) and Osprey (bottom left) are located on Bennu’s equatorial region. Site Sandpiper (bottom right) is located on Bennu’s southern hemisphere. Nightingale was chosen as the sample collection site. CREDITS: NASA/Goddard/University of Arizona
Given Bennu’s unexpectedly rough terrain, NASA’s OSIRIS-REx team took extra time to evaluate potential sample collection areas. They looked for flat surfaces between numerous rugged boulders. They also looked for regions with fine grains on the surface that the spacecraft could easily ingest. Through their own analyses and a public mapping campaign, the mission team first identified more than 50 sites, whittled those down to 16, and then to the final four candidates. The spacecraft then spent a month investigating each of the four sites and sending home images so scientists could further evaluate them.
A spot dubbed “Nightingale” by the team, set in a small crater, rose to the top of the list in December 2019. The size of a few parking spaces, Nightingale was the most promising location to meet both safety and sample-availability considerations. But it wasn’t perfect. The area was only about one-tenth the size the mission team had planned for. This put pressure on OSIRIS-REx navigation engineers to program the spacecraft to dodge boulders, such as a building-size one, nicknamed “Mount Doom,” during its 2020 autonomous navigation to a small spot on the surface.
This week, we are recapping noteworthy OSIRIS-REx mission events each day so you can catch up on anything you may have missed so far in NASA’s first mission to collect a sample from an asteroid.
(Post #2 in a series of four)
After traveling 1.2 billion miles (2 billion kilometers) to Bennu, NASA’s OSIRIS-REx spacecraft arrived in December 2018 and began orbiting the asteroid. Until the spacecraft got to Bennu, we could only see the asteroid as a pixelated blob through Earth telescopes and radar measurements. Still, scientists had an idea of what they would find at Bennu by using years of radar and thermal measurements and computer models to predict its mass, shape, and surface features.
On the left, a compilation of radar images of asteroid Bennu. On the right, a shape model based on radar imaging and visible light curves. CREDITS: Michael C. Nolan / Arecibo Observatory / CC BY-NC-ND 3.0
In early 2019, OSIRIS-REx began to study Bennu in detail. The spacecraft zigzagged Bennu in a trajectory that looked like a child’s sweeping crayon sketch. The first closeup images of the asteroid revealed surprises that would require scientists to update some of the fundamental assumptions used in their predictive computer models.
Instead of there being a smooth, sandy beach on the surface that the mission team had expected to see, Bennu was littered with boulders and was spewing rock particles into space. It became clear that safely navigating to the surface would be an unexpected challenge. The mission team would spend most of the next year mapping Bennu in detail and looking for a relatively smooth area with the fewest hazards and the most opportunity to gather scientifically interesting samples.
This week, we are recapping noteworthy OSIRIS-REx mission events each day so you can catch up on anything you may have missed so far in NASA’s first mission to collect a sample from an asteroid.
(Post #1 in a series of four)
NASA’s first mission to sample an asteroid, OSIRIS-REx, launched on Sept. 8, 2016, at 7:05 p.m. EDT from Cape Canaveral Space Force Station in Florida. About the size of an S.U.V., OSIRIS-REx would travel for two years to a near-Earth asteroid originally designated 1999 RQ36. The name “Bennu,” referencing an ancient Egyptian deity, was picked in 2013 by nine-year-old Michael Puzio, from North Carolina, who won a naming competition.
NASA chose to go to Bennu because the asteroid possesses several key characteristics that make it perfect for a sample return mission. Here are all the reasons why.
Scientists around the globe have been waiting for years for the spacecraft to deliver a sample from Bennu to Earth. Among the many questions they’ve been waiting to explore by analyzing pieces of Bennu is: Did asteroids deliver molecules that played a role in the origin of life on Earth, and potentially on other planets and moons?
After seven years in space, including a nail-biting touchdown on Bennu in 2020 to gather up dust and rocks, NASA’s intrepid OSIRIS-REx spacecraft is about to face one of its biggest challenges yet: deliver an asteroid sample to Earth while protecting it from heat, vibrations, and earthly contaminants.
“Once the sample capsule touches down, our team will be racing against the clock to recover it and get it to the safety of a temporary clean room,” said Mike Moreau, deputy project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
