SO Web-Colloquia: Osiris-Rex: results on a mission to understand planetary systems

In September 2016, the NASA OSIRIS-REx spacecraft was successfully launched from Cape Canaveral Air Force Station, in Florida. That was the beginning of an amazing journey to reach near-Earth asteroid Bennu, collect a sample of material from its surface, and bring it back to Earth in 2023. The so-called “Touch-And-Go” maneuver or TAG, took place on October 20, 2020 and the sample collector head has been safely placed into the Sample Return Capsule. Images obtained from a series of cameras on-board the spacecraft show that the collector head is holding much more than 60 g of material (the mission’s minimum requirement). Bennu is a primitive, carbon-rich asteroid, containing organic and water-bearing minerals like clays. These type of asteroids have not significantly changed since they formed nearly 4.5 billion years ago, and therefore are considered relics from the early stages of our Solar system. The OSIRIS-REx mission will bring for the first time pristine material from such early epoch, that will be analyzed in the laboratory and will help scientists to confirm if asteroids are a source of the water and organic molecules that may have made their way to Earth and other planetary bodies early in their histories. In addition, Bennu is one of the most potentially hazardous asteroid (PHA), coming close to Earth every six years. OSIRIS-REx mission spent two years orbiting and studying in detail the surface of this extremely interesting asteroid. I will go through the main findings provided by the data obtained with the instruments on-board the spacecraft, including the discovery of a rough, rocky surface, the unexpected particle ejection events, or a collection of bright, silicate-rich boulder having an exogenous origin.