More than four years after it launched from Cape Canaveral, NASA’s Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) probe finally approached its mission destination.

The craft briefly landed on the surface of the asteroid Bennu, currently 200 million miles from Earth, on October 20, 2020, and collected samples of surface material. A planetary remnant, Bennu is about as tall as the Empire State Building and contains pristine material from the formation of the solar system about 4.5 billion years ago, potentially including the organic molecular precursors to life on Earth.

Its 11 ft Touch-And-Go (TAG) Sample Acquisition Mechanism successfully touched the asteroid surface and fired a nitrogen gas canister to agitate and retrieve material through a filter in the round sampler head. Ten minutes NASA’s OSIRIS-REx mission depicted as it readies itself to touch the surface of asteroid Bennu. Source: NASA Goddard Space Flight Center/University of Arizonalater, the spacecraft fired its thrusters to slow its descent and match the asteroid’s rotation at the time of contact.

The researchers will need about one week to determine how much material was collected. The mission's goal is to harvest at least 60 g of regolith and potentially collect up to 2 kg. Imagery from the TAG event will also be analyzed to assess how the surface of Bennu responded to the TAG event. These observations will also aid in identifying and measuring the sample size remotely.

A second chance awaits the spacecraft if NASA engineers determine that a larger-sized souvenir from Bennu is needed. If it is, another TAG maneuver on the boulder-covered space rock will be attempted on January 21, 2021.

OSIRIS-REx is expected to depart Bennu in March 2021 for its long journey back to Earth, with a planned landing in the Utah desert in September 2023.