Chapter 8 - OSIRIS-REx at Bennu: Overcoming challenges to collect a sample of the early Solar System

Abstract

The Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS-REx) spacecraft arrived at its target, near-Earth asteroid (101955) Bennu, in December 2018. Observations by the onboard instruments revealed an asteroid substantially different from pre-encounter expectations, including a rough and rugged terrain that complicated the mission’s objective of collecting a sample. The team altered the mission profile to accommodate the reality of the target and incorporate lessons learned during operations. The data acquired by the OSIRIS-REx spacecraft at Bennu characterized this primitive asteroid’s physical, chemical, and geological properties and provided critical context for the collected sample. In December 2019, after a year of operating in proximity, the team selected primary and backup sites for sample collection. In October 2020, OSIRIS-REx descended to the Bennu surface and collected a sample from the primary site, Nightingale. The spacecraft departs Bennu in 2021 and will return the sample to Earth in September 2023.