NASA’s Osiris-Rex spacecraft touches down on asteroid Bennu
Four yearsNASA’s Osiris-rex historically and briefly landed on the potentially dangerous asteroid Bennu, over 200 million miles away.
The spaceship traveled all the way to perform a brief touch-and-go maneuver with the aim of collecting a sample from the surface of the asteroid and transporting it back to Earth for investigation.
We won’t know until Wednesday if Osiris-rex managed to get hold of a space science souvenir, but on Tuesday NASA TV reported that the spacecraft’s robotic sampling arm called the Touch-and-Go Sampling Mechanism (TAGSAM) Bennu was successful touched down about fifteen seconds. A cosmic pickpocketing maneuver was carried out during the brief contact.
The spaceship, which works largely autonomously due to the 18-minute communication delay with mission control on Earth, fired a gas canister through TAGSAM, which should have disrupted the surface of Bennu so far that a sample could get into the collecting head of the arm.
The team’s goal is to collect about 60 grams of dust, dirt, and pebbles from the surface of Bennu. To determine if this goal has been achieved, Osiris-rex will maneuver into a safe position in the coming hours and then position its arm to take photos of the collector’s head and weigh how much mass there is in it.
There is no guarantee that Osiris-rex collected a significant sample. As the spaceship approached and then circled and examined Bennu for two years, it became clear that this tiny world is different from what scientists expected. The team hoped to find a number of sandy surfaces ideal for sampling, but it turns out Bennu is a heap of rubble with a rough terrain full of boulders.
Osiris-rex was designed to sit on a level surface, but Bennu is so rocky on the surface that the team couldn’t find a suitable spot. Fortunately, Osiris-rex seems to outperform its design when it comes to precision navigation. This gave the team the confidence to attempt their sampling maneuver in an area called Nightingale, which is only about the size of some parking lots.
Given the landscape, there are a number of things that could go wrong if, for example, Osiris-Rex cuts off a boulder or hits an uneven surface at a strange angle. If this turns out to be the case, we will find out on Wednesday and Osiris-Rex will begin preparing for a second attempt at one of the selected backup locations. The spaceship is equipped with three cylinders of nitrogen gas, so if the sample is successfully taken, the team should receive at least two more shots.
If Osiris-Rex is successful, he will join the Japanese Hayabusa andin the annals of asteroid exploration. Hayabusa has successfully collected and returned a small piece of material from the Itokawa asteroid, and Hayabusa2 is in the process of returning a significant sample of the Ryugu space rock.
Should the mission collect a sample, a long journey back to Earth begins with a scheduled landing in the Utah desert in September 2023.