Asteroid Bennu is slated for a close encounter with Earth in 2175. It is expected to be the asteroid that has the most chance for a possible Earth impact over the next 200 years. Hence, it was selected for NASA’s OSIRIS-REx mission.
Mat Kaplan at Planetary Radio sat down to discuss the mission with it’s Principal Investigator, Dante Lauretta. The mission is of interest because it will descent on Bennu’s surface in August 2020, collect a sample and return it to Earth in 2023. These are my podcast notes from that episode.
Lauretta talks about the mission updates till now. The spacecraft reached the asteroid and has been doing a series of mapping the surface of the asteroid. In December 2019, they selected the landing site, code-named Nightingale. All surface features on Bennu named so far are named after Egyptian birds. Bennu itself is named after an Egyptian mythological bird, that probably inspired the Greek bird, the phoenix.
He then talked about the surprise of finding the surface of the asteroid so rocky. Apparently, radio and infrared studies of the asteroid’s surface had predicted the surface to be smooth. They had designed the instruments using the experience gained on the Hayabusa spacecraft which had a 25-meters radius for operations. They had given themselves a 50-meters radius for operations. But, the current landing site gives them just 5-meters. This means that they had to drop the LIDAR based landing navigation system and use a more optical based hazard avoidance system to land on the surface.
He then talked about cross-pollination between the Hayabusa and the OSIRIS mission with people working in each other’s projects. This is part of the on-going collaboration between NASA and JAXA.
They then spoke about some of the public outreach efforts of the mission. This is usually an integral part of all NASA missions. However, OSIRIS’ education and public outreach budget was cut in 2018. Lauretta then took it upon himself to continue the work. He designed board games and also supports Target Asteroids!, a program that takes help from amateur astronomers to observe certain asteroids. The board games include X-tronaut and Constellations.
Unrelated, but the episode ends with a session of Space Poetry.
Parallel Spirals 
