Webb Telescope detects new population of small Main Belt Asteroids

A team from the Massachusetts Institute of Technology (MIT) used Webb's observations of the star TRAPPIST-1 to identify 138 new asteroids ranging in size from a bus to a stadium. These detections, made possible by repurposing Webb's infrared imaging capabilities, offer new insights into asteroid formation and the evolution of the main belt over time.

"These findings enhance our understanding of how small objects in the asteroid belt are formed and their potential trajectories," explained Tom Greene, an astrophysicist at NASA's Ames Research Center and co-author of the study. He noted that such objects likely originate from collisions among larger asteroids and may drift closer to Earth and the Sun.

The study's methodology involved analyzing over 10,000 images of TRAPPIST-1, initially captured to investigate planetary atmospheres, for the faint traces of asteroids crossing Webb's field of view. This innovative approach leveraged the brightness of asteroids in infrared light, which Webb is optimized to detect, enabling researchers to uncover asteroids in size ranges previously unobservable with ground-based telescopes.

"This work underscores the versatility of Webb's capabilities," said Jessie Dotson, an astrophysicist at Ames and a member of NASA's Asteroid Threat Assessment Project (ATAP). "Understanding these smaller main belt asteroids provides vital context for studying near-Earth objects, which are crucial for planetary defense."

The findings contribute to ongoing efforts at NASA's Planetary Defense Coordination Office, where ATAP models the risks and impacts of potential asteroid collisions with Earth. These insights are expected to enhance planning and mitigation strategies for planetary defense.

NASA also plans to extend the use of infrared technology in asteroid research with the Near-Earth Object (NEO) Surveyor mission. This upcoming space telescope will specialize in detecting asteroids and comets that could pose a threat to Earth.

The research team, led by MIT's Artem Burdanov and Julien de Wit, emphasized the importance of Webb's ability to detect faint, previously unnoticed objects. Their work provides a foundation for future studies of asteroid dynamics and their implications for both science and safety.

Research Report:Detections of decameter main-belt asteroids with JWST