OSIRIS-REx Science Chief Reveals NASA's 1st Asteroid Sampling Mission Nearly Didn't Make It

On September 24, NASA's groundbreaking OSIRIS-REx spacecraft is scheduled to achieve a historic milestone by delivering a piece of the asteroid Bennu to Earth. However, the journey leading up to this momentous occasion was not without its share of challenges, as revealed by Dante Lauretta, the chief scientist of the OSIRIS-REx mission, in an exclusive interview with Space.com.

Named after an ancient Egyptian king of myth who faced his own set of trials, the OSIRIS-REx mission encountered its fair share of obstacles, primarily in the form of its target asteroid, Bennu. The mission, which stands for Origins Spectral Interpretation Resource Identification Security Regolith Explorer, aimed to shed light on the origins of life in the solar system.

During the interview, Lauretta, who also holds the position of a planetary science professor at the University of Arizona, recounted how the mission had to adapt to unforeseen challenges. One of the most significant hurdles was the discovery that Bennu's surface differed greatly from initial expectations. Instead of a smooth area ideal for sampling, the asteroid's surface was strewn with large rocky boulders.

"The surface was covered with large, rough and rocky boulders everywhere and there were no smooth areas of the kind that we designed the spacecraft to go down and sample," Lauretta explained.

This unexpected surface texture forced engineers to reprogram the spacecraft's landing approach, transitioning from relying on a laser altimeter to using onboard cameras for navigation. The team also conducted an extensive mapping campaign to ensure the spacecraft could identify a safe landing site amidst the hazards.

Another unexpected challenge arose during the actual sample collection attempt. The spacecraft's sampling device, known as TAGSAM (Touch-and-Go Sample Acquisition Mechanism), encountered unexpected behavior upon contact with the asteroid. The surface lacked the resistance the team had anticipated, resulting in the spacecraft sinking much deeper than intended during the brief touchdown. Thankfully, the spacecraft's systems allowed it to safely withdraw from the surface with the collected sample.

Throughout the interview, Lauretta discussed the mission's implications for understanding asteroids, the potential for future deflection missions, and the collaboration with musician and stereoscopic imaging expert Brian May, who aided the team in assessing the asteroid's rugged surface.

Regarding the upcoming sample return to Earth, Lauretta expressed anticipation, revealing that the first scientific analyses could be available within days of the sample's arrival. He noted that the team is prepared for the possibility of surprises, considering the unique nature of Bennu.

The OSIRIS-REx mission, which has been in preparation for nearly two decades, is expected to provide valuable insights into the origins of our solar system and the potential threat posed by near-Earth asteroids. As the spacecraft's journey comes full circle with the imminent sample delivery, the scientific community and the world await the treasure trove of information that may reshape our understanding of the cosmos.