NASA’s OSIRIS-REx Mission Successfully Returns Asteroid Sample, Potentially Offering Insights into Solar System’s Formation

On Sunday, September 24, 2023, NASA’s OSIRIS-REx mission’s sample return capsule successfully landed at the Department of Defense’s Utah Test and Training Range. The capsule held a sample gathered from the asteroid Bennu in October 2020. Photo credit goes to NASA/Keegan Barber.

Expert Richard Binzel elaborates on how the asteroid material returned by OSIRIS-REx, in collaboration with MIT, could provide valuable information about the genesis of our solar system.

In the early hours of September 24, a mini-fridge-sized capsule descended from the sky above western Utah. It contained an unprecedented cargo: roughly 250 grams of soil and particulate matter taken from an asteroid’s surface. The capsule’s descent was aided by a striped parachute, allowing it to land ahead of schedule on the desert sand below.

This unique payload was brought back by OSIRIS-REx, NASA’s inaugural mission to retrieve an asteroid sample and return it to Earth. Initiated in 2016, the mission aimed to explore Bennu, a near-Earth asteroid believed to have formed within the first 10 million years of our solar system’s existence. Composed primarily of carbon and minerals, the asteroid has undergone minimal changes since its formation. Thus, its surface material could yield important insights into the substances that initially shaped our early solar system.

The sample return capsule from NASA’s OSIRIS-REx mission is seen shortly after touching down in the desert, Sunday, September 24, 2023, at the Department of Defense’s Utah Test and Training Range. The sample was collected from the asteroid Bennu in October 2020 by NASA’s OSIRIS-REx spacecraft. Photo credit goes to NASA/Keegan Barber.

The OSIRIS-REx spacecraft took over two years to reach Bennu and then spent another two years orbiting the celestial body, surveying its surface to identify an appropriate site for sampling. One of the key tools on board was an experiment designed by MIT students, known as the Regolith X-ray Imaging Spectrometer (REXIS). This compact device was engineered by over 100 MIT students and was created to chart the asteroid’s surface in X-ray wavelengths, assisting in the selection of a suitable sample site. The REXIS project was a collaborative effort between various departments at MIT, the Harvard College Observatory, the MIT Kavli Institute for Astrophysics and Space Research, and MIT Lincoln Laboratory.

On the aforementioned date, the capsule re-entered Earth’s atmosphere, while OSIRIS-REx redirected its trajectory towards another asteroid, Apophis. The capsule has since been moved to Johnson Space Center in Houston, where the material from Bennu will be studied and distributed globally for additional research. The successful return of the sample marks a significant achievement for the mission’s team, including Richard Binzel of MIT, a prominent figure in asteroid research. Binzel, who is a post-tenure professor in MIT’s Earth, Atmospheric and Planetary Sciences (EAPS) and Aeronautics and Astronautics (AeroAstro) departments, has been a co-investigator on the OSIRIS-REx mission. He played a pivotal role in the development and integration of REXIS into the spacecraft. MIT News sought Binzel’s initial thoughts after the landing and potential implications of the study of Bennu’s material.

Q: Your reaction to this landmark landing, especially as an expert in asteroid study?

A: The experience was tense and emotionally charged, much like the collective relief one feels when a gymnast successfully completes a balance beam routine. Though I was not physically present at the landing site, a sense of communal accomplishment was felt through online interactions. This mission has been over two decades in the making, beginning with our telescopic identification of Bennu as a valuable and accessible target for sampling, leading up to the intricate designs of the mission itself. MIT students have been involved with the REXIS instrument since 2010, culminating in this momentous return of the sample to Earth.

Q: What can the laboratory studies reveal that the spacecraft’s onboard instruments could not?

A: Although the spacecraft’s instruments have been invaluable in suggesting that Bennu is rich in carbon, laboratories on Earth can conduct far more comprehensive analyses. It is only through laboratory studies of the actual samples that we can validate the data collected in orbit and thereby refine our understanding of asteroids and, by extension, the solar system. These Earth-based analyses will permit a deeper exploration into the chemistry, conditions, and processes that led to the formation of our planetary system.

Q: What is the impact of student involvement in a mission of this scale?

A: This mission epitomizes MIT’s ethos of “mens et manus” (“mind and hand”), stretching its application across hundreds of millions of miles in space. The REXIS instrument stands as a testament to the students’ intellectual and practical contributions, extending farther into space than any other MIT student project to date. The mission has been an unparalleled opportunity for students to learn the intricacies of teamwork, dedication, and the complexities of space exploration.

Frequently Asked Questions (FAQs) about OSIRIS-REx Asteroid Sample Return

More about OSIRIS-REx Asteroid Sample Return

• NASA’s OSIRIS-REx Mission Overview
• MIT Department of Earth, Atmospheric and Planetary Sciences (EAPS)
• MIT Department of Aeronautics and Astronautics (AeroAstro)
• Johnson Space Center
• Department of Defense’s Utah Test and Training Range
• Harvard College Observatory
• MIT Kavli Institute for Astrophysics and Space Research
• MIT Lincoln Laboratory
• Asteroid Bennu
• Asteroid Apophis