NASA’s pioneering OSIRIS-REx probe has returned its precious asteroid samples to Earth.
Task force members announced on Thursday (October 29) that OSIRIS-REx has completed the storage of the carbon-rich asteroid Bennu captured last Tuesday (October 20) and successfully locked it in the spacecraft The return cabin.
Team members said that the samples seemed to be plentiful-heavier than the 2.1 ounce (60 grams) target set by the mission. Indeed, OSIRIS-REx collected so much material on October 20 that its sampling head could not be closed properly. The sealed mylar flaps on the head are wedged into place by protruding Bennu pebbles.
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The OSIRIS-REx team noticed the problem when inspecting the head photos and samples collected last week. Fragments of escaped asteroid material float across the frame. In order to minimize losses, the team decided to speed up the precise and complex storage procedure, which should have been carried out next week.
Therefore, in the course of 36 hours on Tuesday and Wednesday (October 27 and October 28), the engineer instructed OSIRIS-REx to put the sampling head at the end of the probe’s robotic arm into the return capsule. Drag the head to ensure proper fixation; disconnect from the robotic arm; and lock the return capsule by locking the two latches.
All this was done when OSIRIS-REx was about 205 million miles (330 million kilometers) away from the earth, which means that it takes 18.5 minutes for each command to reach OSIRIS-REx, and each time it returns from the probe to the update. It takes 18.5 minutes to earth.
Sandra Freund, OSIRIS-REx mission operations manager at Lockheed Martin Aerospace in Littleton, Colorado, said at a NASA press conference on Thursday: “We only want to try to collect I just want to ensure success.” “And we must be.”
The planned changes require a last-minute reallocation of time on NASA’s Deep Space Network (DSN), the agency’s radio telescope system used to communicate with long-range probes. Because storage operations are very important and involve a lot, OSIRIS-REx requires a lot of continuous DSN time, and other NASA missions have paid a greater sacrifice for this.
It is unclear how many asteroid materials are currently in the return capsule of OSIRIS-REx, which will land on Earth in September 2023. The team canceled the planned post-sampling weighing procedure, which would involve rotating the probe, because this operation would cause more sample loss. (The task team member explained that moving the arm (for example, taking a sample and putting it away) gave the grain an acceleration. Therefore, they wanted to minimize this movement.)
However, Dante Lauretta, mission lead researcher at the University of Arizona, said there must be a lot of asteroid material on board.
Lauretta said that the sampling operation on October 20 went very well, and the head went deep into Bennu’s surface-possibly 19 inches (48 cm) or more. The team is confident that OSIRIS-REx was almost full of sampling heads that day, which means it may be far away from Bennu with a weight of about 4.4 pounds. (2 kg) collected materials.
In comparison, Lauretta said, the losses in the next few days appear to be small-possibly “tens of grams” in total. Recent photos of the sampling head show that it is still packed. Laureta said the task force members could only see 17% of the head volume in these photos, but they estimated that approximately 14.1 ounces (400 grams) of Bennu material was stuck in the space.
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If the estimate is accurate, and if 17% of the slices represent the entire sampling head, the weight of OSIRIS-REx may exceed 4.4 pounds. (2 kg) samples. Lauretta’s overall forecast is more measurable than this, but still definitely bullish.
Laureta said at today’s press conference: “I believe there are still hundreds of grams of material in the sample collection head, which can easily exceed one kilogram.”
That will be good news. Such a large number will enable many research groups to study Bennu’s soil and rocks, and conduct various experiments on primitive samples of the universe. For example, Lauretta points to organic chemistry, especially the analysis involving sugars.
Sugar” is expected to be present in very low abundance [on asteroids like Bennu]Lauretta said, “A few grams of samples need to be extracted from it. We think 15-gram distribution will not be feasible, but as the amount of analysis increases, this situation does exist.”
(The OSIRIS-REx scientific team can analyze up to 25% of the returned samples. If the final total sample size is the target 60 grams, the team can study up to 15 grams of samples.)
If everything goes according to plan, such experiments will reveal the early development of the solar system and the role of asteroids like Bennu in helping life to reach the earth by transporting large amounts of water and carbon-containing organic chemicals. . The main goal of the US$800 million OSIRIS-REx mission is to solve these major problems. The mission was launched in September 2016 and reached Bennu in December 2018.
The next major step of the task is to prepare for the return journey (although the engineers are still trying to figure out whether they can somehow make a rough estimate of the quality of the samples now stored). Team members said today that the orbital dynamics indicated that OSIRIS-REx must start returning home between early March and May, and the current plan is to target the earliest part of the window.
OSIRIS-REx is NASA’s first asteroid sampling mission, but this is not the first in history. Japan’s Haytori mission sent a small amount of the rocky asteroid Itokawa into the earth in 2010. The probe’s successor, Nitori-2, is scheduled to return samples of the carbon-rich asteroid Ryugu in December.
Mike Wall is the author of Out Central (Grand Central Press, 2018; illustrated by Karl Tate), a book on the search for alien life . Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.