Bennu Tag
The Osiris-REx mission is due to touch down on asteroid Bennu today. The craft will descend in microgravity, touch down, collect a sample and return it to Earth.
The probe is about the size of a minibus, and it is currently orbiting Bennu.
The touchdown will be in a site in the Northern Hemisphere of Bennu, dubbed “Nightingale”. The craft will have to make decisions autonomously in the landing, as Benny is so far away a radio signal would take 18.5 minutes to arrive. It will do this by using cameras to track geographic features on the surface of the asteroid, and it has the authority to ‘wave off’ the mission if it cannot land within the designated area.
After the collection, on Oct 22, the spacecraft will use a camera to check if a sample has been obtained, and on Oct 24, the sample will be spun to check there is an appropriate amount. If all is well, the sample will be returned. If the collection is not successful, then another attempt can be made in 2021.
The sample is due back on Earth in Sept 24, 2023.
The manoeuvre starts at 1:50pm EDT on Oct 20th, 6:50pm UK time. NASA TV begins coverage at 5pm EDT (10pm UK time). Sample collection will be at 6:12pm EDT (11:12pm UK time)
Links
Images from the dress rehearsal (a close pass that did everything but land)
