Asteroid Bennu Samples Arrive on Earth: How OSIRIS-REx Made History

A historic mission to collect a piece of an ancient asteroid has reached its final stage, as a capsule containing precious samples from the space rock Bennu safely landed on Earth on Sunday, September 24, 2023.

The capsule, which was part of NASA's OSIRIS-REx spacecraft, descended from orbit and entered the atmosphere at a speed of over 27,000 miles per hour. It deployed parachutes and touched down at a site near Salt Lake City, Utah, at 8:52 a.m. local time.

A recovery team quickly located the capsule and transported it to a nearby facility, where it was sealed in a nitrogen-filled container to prevent any contamination from Earth's air. The capsule holds about 8.8 ounces of dust and pebbles from Bennu's surface, which could reveal clues about the origin of life and the formation of planets.

The samples will be flown to NASA's Johnson Space Center in Houston on September 25, where they will be stored and analyzed by scientists from around the world. The capsule will remain unopened until then, preserving the pristine quality of the asteroid material.

The OSIRIS-REx mission, which stands for Origins, Spectral Interpretation, Resource Identification and Security – Regolith Explorer, was launched in September 2016 and reached Bennu in December 2018. The spacecraft spent two years surveying the asteroid and selecting a suitable site for sampling.

On October 20, 2020, OSIRIS-REx briefly touched down on Bennu and used a robotic arm to blast the surface with compressed gas and collect the resulting debris. The spacecraft then began its journey back to Earth on May 10, 2021, carrying the precious cargo.

Bennu is a carbon-rich asteroid that is about 1,600 feet wide and orbits the sun every 1.2 years. It is one of the oldest and most primitive objects in the solar system, dating back to more than 4.5 billion years ago. Scientists hope that by studying its composition, they can learn more about how our planet and other worlds came to be, as well as how organic molecules and water were delivered to Earth.

The OSIRIS-REx mission is the first U.S. mission to return samples from an asteroid, and the largest sample return since the Apollo moon missions. It is also the third successful asteroid sample return mission in history, following Japan's Hayabusa and Hayabusa2 missions.