Soon, the OSIRIS-REx spaceship will begin NASA’s first-ever trial to reach the ground of an asteroid. Then, it must gather some samples and return safely. But since landing on asteroid Bennu last year, the mission team still needs to figure out how to do all of that on an asteroid’s surface.
Bennu is covered in building-sized rocks. The team succeeded, however, by utilizing those hazardous rocks as signposts, to make a new accurate navigation procedure to overcome the challenge.
The OSIRIS-REx mission team had initially scheduled to utilize a LIDAR technology to navigate to Bennu’s ground during the TAG (Touch-And-Go) sample collection task. LIDAR uses laser pulses instead of radio waves to calculate length. The OSIRIS-REx GNC (Guidance, Navigation, and Control) LIDAR is developed to navigate the spaceship to a relatively hazard-free ground.
Asteroid Bennu’s Rocky Surface Troubles NASA’s OSIRIS-REx Mission
Also, the mission had initially foreseen a touchdown site 50 meters in diameter, but the most prominent safe places on Bennu are much smaller. The most massive, for example, is only 16 meters, or almost 10 % of the safe zone foreseen. The team knew that they needed a more accurate navigation method that would let the spaceship to target tiny sections while avoiding potential hazards precisely.
Moreover, in the face of such a daring task, the OSIRIS-REx team shifted to a new navigation technique dubbed NFT (the National Feature Tracking). Such a process offers more widespread navigation skills than LIDAR. It is also significant for performing what the team is nicknaming “Bullseye TAG,” which send the spaceship to a much smaller sampling place.
A catalog to spot rocks and craters is also required to the sample site area and will upload the data to the spaceship before the sample gathering event. As for Bennu’s surface, the team developed “hazard maps,” for both Osprey and Nightingale sites to document all of the ground characteristics that could harm the spaceship.