NASA’s OSIRIS-REx mission almost quieted down, and then Queen guitarist Brian May stepped in
On September 24, NASA The OSIRIS-REx spacecraft It will hurtle back through Earth’s atmosphere after a years-long voyage to Bennu,”potentially dangerous asteroidWith a 1 in 2,700 chance of catastrophically hitting Earth, the highest odds of any space object identified.
The aim of the mission? To find out if life on Earth came from outer space. But for 22 exciting months, scientists wondered whether they would be able to land a spacecraft on the asteroid at all.
The mission’s eventual success is due in part to Queen’s guitarist, Brian May, who meticulously created 3D images of the rubble heap to help mission commanders determine safe landing spots. Thanks to this safe landing, OSIRIS-REx is now returning from its mission with a 2-ounce (60-gram) sample from Bennu’s surface that could contain precursors to extraterrestrial life on our planet.
Related: The building block of life has been discovered on the distant asteroid Ryugu, and it could explain how life began on Earth
“I thought asteroids They are pieces of junk that might befall us and we’re so afraid of them – whatever. “You don’t actually realize that, they’re probably responsible for us being here,” May, who also has a doctorate in astrophysics, told Live Science. “Maybe there would be no biosphere without asteroids. And maybe the actual seeds of life came from them too, which is an incredible idea. So asteroids definitely become the center of everything: if we understand asteroids, we will understand ourselves.”
Benu: Bringer of death, god of creation
Viewed from a distance, Bennu looks like an inert, debris-filled spinning top suspended in space. Classified as a rubble-pile asteroid, Bennu is an 85.5 million ton (77.5 million metric ton) collection of bits of rock and rock that barely holds together because of weak gravity — a cosmic spherical crater that swallows any object that lands hard on its surface. It sends anything that is powerfully launched from it into space.
However, get closer, as OSIRIS-REx did on its first approach in 2018, and a quite strange picture emerges. 3-foot-long (0.9-meter) veins of carbonate rock criss-cross a surface strewn with carbon-rich organic material — evidence of Bennu’s parent body, a 60-mile-wide (96-kilometer) body that formed during the early years of the solar system and split about A billion years ago to form, the asteroid was once home to torrents of hot water and the building blocks of the first life.
Bennu is named after the ancient Egyptian god of creation, and the OSIRIS-REx (short for Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) journey to the asteroid was nothing short of epic. It launched from Florida in 2016 and orbited Earth before reaching Bennu’s orbit in December 2018.
Stick to the landing
However, not only did OSIRIS-REx need to reach Bennu, the real trick was to land. Initial thermal surveys of Bennu seemed to indicate that it was composed of fine-grained material, much like a beach, according to the mission commander. Dante LorettaProfessor of Planetary Sciences and Cosmic Chemistry at the University of Arizona.
But when OSIRIS-REx finally arrived, it encountered a rocky asteroid littered with sharp boulders, rendering the original landing strategy, which relied on a laser altimeter to measure altitude, completely useless. Instead, the team pushed the spacecraft into a tight orbit using Bennu’s weak gravity, making thousands of passes over the rock’s surface to search for a safe landing spot.
“Yes, we were challenged to find a safe place on the asteroid to send our billion-dollar spacecraft down to collect a sample,” Loretta told Live Science. “I mean, this isn’t an easy decision, and it was my decision, right? I was in trouble because of this.”
To find a suitable parking spot on Bennu, OSIRIS-REx scientists used cameras on board their spacecraft to precisely map its surface features down to the centimeter. Then, by taking pairs of side-by-side images, taken by Brian May and his collaborator Claudia Manzoni They cropped them together to create stereoscopic images (created by stitching two images together to recreate the eyes’ depth perception) – enabling the team to fully assess the safety of potential landing sites.
“We look at flat images and think: ‘Well, this might be good, it looks reasonably safe and flat,’ and then suddenly 3D appears and we say: ‘Err, no,’” Loretta said.
Loretta added, “Brian was processing scene after scene and I was worried we’d never be able to find a sampling location.” “Until the end, we saw these little bowl-shaped craters, maybe 10 or 20 meters wide, filled with this fine-grained material. Then I realized we were on to something.”
After 22 months of fraught deliberation, researchers settled on a site they called Nightingale, which OSIRIS-REx touched down on October 20, 2020. To continue its descent and avoid completely plunging through the asteroid’s rubble-heaped surface, the spacecraft fired a rapid blast of nitrogen gas. Through the Touch Screened Sample Acquisition Mechanism (TAGSAM).
Besides providing the spacecraft a precarious foothold on Bennu’s surface, TAGSAM sent dust and crushed rock flying in all directions, most importantly into the OSIRIS-REx sample chamber, which collected so much more material than expected that it had trouble shutting down for a while. brief.
What’s in the box?
Exactly what is hiding among the rocks collected in the OSIRIS-REx sample cannot be guessed, but the possibilities are exciting, mission scientists say.
“We don’t know until we get them, but just looking at the pictures Dante and Brian sent, they appear to be filled with a lot of different types of rocks, some of which are very fragile, which means they will never make it to Earth as meteorites.” Sarah RussellProfessor of Planetary Sciences and head of the Planetary Materials Group, which will analyze part of the sample at London’s Natural History Museum, told Live Science. “I hope it tells us something we didn’t even know we didn’t know.”
The story of the journey of asteroid Bennu and OSIRIS-REx is told in a new book filled with Brian May’s photographs. It also features a 3D eye designed by the rock god himself. “Bino: Anatomy of an Asteroid in 3D,” written by Dante Lauretta, Principal Investigator, OSIRIS-REx, is available in the US from University of Arizona Press and in the UK from London Stereoscopic.
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