NASA’s OSIRIS-REx asteroid probe has done a lot of preparatory work in the near future. After successfully reaching the orbit of the space rock Bennu in 2018, the work at this stage is to prepare for landing on the space rock. As it turns out, Bennu’s surface is littered with more debris than NASA expected, so finding a landing area that can land offers a huge challenge.
In December 2019, NASA chose the landing zones of Nightingale and Osprey. Recently, the NASA team conducted a landing test of the Osprey area at a minimum distance of 250 meters. 350 photos were taken in this test, and NASA stitched it together below. While this is dangerous, it is essential to ensure the ultimate success of the mission.
The Nightingale is located in a 70-meter-wide crater in the northern hemisphere of Benou, with a relatively cool and dark surface that looks like sand, while ospreys are located in a smaller crater closer to the equator.
Now the team has chosen the Nightingale sample point as its primary collection site, but the team also has Osprey sits as an important backup plan. The actual sampling operation is very complex and you can imagine. Before returning to higher orbit, the spacecraft will have to lower itself into the surface straightening arm, stretch its robotic arm and grab samples. The probe will ensure that it collects enough material before setting off, and then, if all goes well, it will automatically exit Bennu’s orbit and is scheduled to reach Earth in 2023.
Geologically speaking, landing on Benu is quite dangerous. OSIRIS-REx needs to fall into an open sandy area on the asteroid’s surface to avoid hitting any large rocks or absorbing rocks larger than 2 cm (which can clog its filters). Mission scientists initially thought that the Benu surface was covered with sandy areas, so OSIRIS-REx could easily perform sampling tasks, but the results showed that Benu’s surface was covered with large rocks and had almost no open areas.
To land in a smaller target area (with a span of 16 meters, rather than the 50 meters that scientists had initially hoped for), mission engineers have been enhancing the spacecraft’s autonomous navigation capabilities. OSIRIS-REx will regularly photograph the asteroid’s surface as it descends, and then decide whether to proceed with the sampling mission. “I’m confident that we’ll get a sample,” said Dante Lauretta, the mission’s chief scientist. “