The spacecraft flew 200 million miles and four years, briefly hit Bennu, exploded it with compressed gas, and collected debris on its surface. On October 21, the space agency shared the first batch of images of the bold operation, revealing the subtle and explosive moments between the rock and the robot.
When the space shuttle’s automatic sampling arm (ie, take-and-go sample collection mechanism) or Tagsam landed on Bennu, it performed an action equivalent to a space pickpocket. Mission planners estimate that the total time for the arm to contact the asteroid will be less than 16 seconds. After the preliminary data was released, it was shown that the contact time was only six seconds, while most of the sample collection only occurred in the first three seconds.
The spacecraft operated largely autonomously due to the 18-minute communication delay required for mission control on Earth. It launched a gas canister through Tagam that destroyed the surface of Bennu and forced the sample into the arm’s collection器头。 Head.
A head photo taken on October 22nd showed that there were too many samples collected, so that some of the larger rocks seemed unable to enter the interior completely. A polyester film sheet was wedged in to partially open the container to allow a small amount. The dust and pebbles escaped back into space.
The sample storage was originally scheduled for November 2, but NASA changed the multi-day program to Tuesday.
Dante Lauretta, the lead researcher of OSIRIS-REx at the University of Arizona, said in a statement: “The large amount of material we collect from Bennu allows us to speed up the storage decision.”
Osiris-Rex marker boulder
As the spacecraft approached, and then spent two years circling and surveying Bennu, it was obvious that this tiny world was different from what scientists expected. The team hoped to find many ideal sandy surfaces for sampling, but it turned out that Bennu was a pile of rubble, and the uneven terrain was full of boulders.
About 24 hours after the space flight, NASA shared the first images of landing operations captured by the spacecraft. Tagsham moved into position, with its sampling head in contact with Bennu’s surface before the explosive nitrogen explosion. The action caused a large amount of debris, which flew around the collection arm. It really is!
Although the GIF above looks relatively fast, the operation is more refined. When the arm touches the sample location, the arm descends at a speed of 10 cm per second, which is much slower than walking.
The team’s goal is to collect about 60 grams of dust, dirt and pebbles from Bennu’s surface. It reported on October 23 that it believed that Osiris-Rex had collected enough samples and acted to begin storing it quickly, skipping planned sample mass measurements and canceling brake burns to maintain the acceleration of the spacecraft At the lowest level.
Lauretata said: “We are trying to maintain our success here, and my job is to return as many Bennu samples as possible safely.”
Although the procedure of collecting samples is done automatically by the spacecraft, the process of storing samples is much slower and requires step by step. Mission control sends commands and evaluates the results before proceeding to the next step.
The mission is with Japan’s Hay Bird Team andIn the annals of asteroid exploration. Abbird took samples from the asteroid Itokawa and returned a small amount of material, while abbird 2 is returning a large number of space rock Ryugu samples.
Now that the samples are stored on Osiris-Rex, the team will begin preparations for the long journey back to Earth, planning to land in the Utah desert in September 2023.