NASA’S OSIRIS-REx Mission
NASA’s OSIRIS-REx is a spacecraft that is a rock collector. On October 20, at around 6 p.m., scientists received information that the spacecraft has come across the asteroid Bennu, and has gotten some of the asteroid’s rocks as a sample to bring back to Earth. In December 2018, the OSIRIS-REx arrived at Bennu, where it spent around two years creating maps of the asteroid’s surface and composition (1). The scientists on Earth originally thought that Bennu was smooth and sandy, but the map created by the OSIRIS-REx revealed the landscape actually is rocky. The scientists were worried over where to land the OSIRIS-REx, so they chose a pretty smooth patch inside of a crater.
The OSIRIS-REx did not need to completely land in the crater to complete its mission, so it just hovered over the surface of the crater. The spacecraft used its robotic arm, which has an instrument called the Touch-And-Go Sample Acquisition mechanism attached to it. The instrument touches the asteroid lightly for about six seconds and releases nitrogen gas in order to disturb the pebbles and dust of the surface of Bennu (1).
Signals given from Earth took approximately 18 minutes to reach Bennu, so the OSIRIS-REx performed the sampling of the rocks by itself (1). Even though the OSIRIS-REx is not the first spacecraft to obtain rock samples from an asteroid, with the first being Japan’s Hayabusa mission, it still tried to obtain more rocks than the Hayabusa2 did. The Hayabusa2 wanted to collect 100 milligrams of rock, but the OSIRIS-REx aimed for a minimum of 60 grams. The OSIRIS-REx will come back to Earth in 2023, which is when scientists will be able to analyze the rocks in order to try and look for the origins of water and life on Earth.
Grossman, Lisa. “NASA's OSIRIS-REx Survived Its Risky Mission to Grab a Piece of an
Asteroid.” Science News, 22 Oct. 2020, www.sciencenews.org/article/nasa-osiris-rex-spacecraft-asteroid-bennu-sample-collection.