NASA’s Osiris-Rex spacecraft lands on the asteroid Bennu with a mission to collect dust | Sciences

A NASA spacecraft has successfully landed on an asteroid, dodging building-sized rocks, to collect a handful of cosmic debris for analysis on Earth.

The space agency team behind the Osiris-Rex project said preliminary data showed that sample collection went according to plan and that the spacecraft had lifted off the surface of the asteroid Bennu.

“I can’t believe we did it,” said lead scientist Dante Lauretta of the University of Arizona. “The spacecraft did everything it was supposed to do.”

NASA Administrator Jim Bridenstine offered his congratulations and said: “We are on track to return the largest sample ever brought from Apollo from space. If all goes well, scientists will study this sample for generations to come. “

The Osiris-Rex spacecraft sent confirmation of its brief contact with the asteroid Bennu more than 200 m miles (322 m km) away, prompting cheers from the mission team. But it could be a week before scientists know how long, if anything, and if another try will be needed. If successful, Osiris-Rex will return the samples in 2023.

The US mission follows a Japanese-led one called Hayabusa2, which is due to return to Earth in December with samples collected from the 4.5 billion-year-old asteroid Ryugu. When it lands in the Australian desert, it will be the first underground asteroid sample to return to Earth.

At Bennu, the Osiris-Rex spacecraft took four and a half hours to descend from its closed orbit to the surface, following commands sent well in advance by ground controllers near Denver.

As the asteroid is only 510 meters wide, Bennu’s gravity was too low for Osiris-Rex to land. As a result, the spacecraft had to extend its 11-foot (3.4-meter) robotic arm and attempt to grab at least 2 ounces (60 grams) of Bennu.

Heather Enos of the University of Arizona, a mission associate scientist, described it as “kissing the surface with a brief touch and voila measured in just seconds.”

The coronavirus pandemic had caused a two-month delay. Tuesday’s operation was considered the most harrowing part of the mission, which began with a launch from Cape Canaveral in 2016.

Osiris-Rex, a spacecraft the size of a pickup truck, targeted a spot equivalent to a few parking spaces on Earth in the middle of the asteroid’s Nightingale crater. After nearly two years in orbit around Bennu, the spacecraft discovered that this location had the largest patch of particles small enough to be swallowed.

After determining that the shoreline was clear, Osiris-Rex approached in the last few yards for sampling. The spacecraft was programmed to fire pressurized nitrogen gas to agitate the surface and then suck in any loose pebbles or dust.

Scientists want between 2 ounces (60 g) and 4 pounds (2 kg) of the black, crumbly, carbon-rich material from Bennu that is believed to contain the building blocks of our solar system.

NASA’s science mission chief Thomas Zurbuchen compared Bennu to the Rosetta Stone, “something that is out there and tells the story of our entire Earth, of the solar system, over the last billions of years.”

Another benefit: Bennu has a slim chance of hitting Earth by the end of the next century, though not as a spectacular end-of-life. The more scientists know about the paths and properties of potentially dangerous space rocks like this one, the better. Osiris-Rex can perform up to three tap-and-march maneuvers in case he falls short. Regardless of how many attempts are needed, the samples will not return to Earth until 2023 to close the search for more than $ 800 million. The sample capsule will be parachuted into the Utah desert.

“That will be another great day for us. But this is absolutely the most important event on the mission right now, ”said NASA scientist Lucy Lim.

Meanwhile, NASA plans to launch three more asteroid missions in the next two years, all one-way trips.

With Associated Press