NASA’s OSIRIS-REx spacecraft appears to have successfully collected a sample from the surface of the Bennu asteroid located 321 million kilometres from Earth.
Bennu was discovered in September 1999 by the LINEAR Project, a collaboration between NASA, the US Air Force, and MIT’s Lincoln Laboratory. The asteroid is believed to have once been a part of a larger body that featured some sort of hydrothermal system. As a result, researchers hope that the samples collected from the surface of Bennu could provide hints about the origin of all life on Earth.
The OSIRIS-REx spacecraft began its preparation for touchdown on the surface of Bennu by completing an initial burn, unfurling its robotic arm, and shifting its solar arrays into the Y-wing configuration.
Following a four-hour descent to the surface of Bennu, the spacecraft executed the “Checkpoint” burn, the first of two maneuvers required to precisely target a predetermined site designated “Nightingale.”
Approximately 10 minutes later, the spacecraft fired its thrusters a second time executing the “Matchpoint” burn. The second of the two final approach maneuvers slowed the spacecraft’s descent and matched its flight path with the rotation of the asteroid.
Following an 11-minute coast phase past a large boulder referred to as “Mount Doom,” the OSIRIS-REx spacecraft successfully touched down on the asteroid’s surface before quickly retreating back into space.
During this brief moment on the surface, referred to as the Touch-and-Go (TAG) event, the spacecraft’s TAG Sample Acquisition Mechanism (TAGSAM) fired a burst of nitrogen gas. The burst was designed to stir up dust and pebbles on the asteroid’s surface which could then be collected by the TAGSAM sample collection head.
Initial data from the spacecraft indicates that the TAG event was executed as planned. However, it will take approximately a week to confirm how large a sample was collected.
If OSIRIS-REx has collected enough of a sample, it will be stowed and teams will command the spacecraft to return to Earth. If the sample is not sufficient, the spacecraft will be prepared for a second TAG event in January.