A University of Hawaiʻi astronomer played a key role in tracking a small asteroid hours before it entered Earth’s atmosphere on December 3, showcasing the critical role Hawaiʻi’s telescopes play in planetary defense.
J.D. Armstrong from the UH Institute for Astronomy (IfA) teamed up with Italian astronomer Marco Micheli to observe the asteroid, known as 2024 XA1, using the Faulkes Telescope North (FTN) atop Haleakalā part of the Las Cumbres Observatory.
The object, which is around 1 meter in length–about the size of a large beach ball–was detected just before entering Earth’s atmosphere, where it created a fireball over Northern Siberia. While no damage was reported, the event highlighted how rapid detection can help prepare for future, more significant threats.
“This was a small object, less than a meter in diameter, and it is unlikely that anyone was injured,” said Armstrong, who also directs IfA’s outreach program, HI STAR. “There are larger asteroids out there that may impact the Earth. The Pan-STARRS and ATLAS observatories on Haleakalā look for these objects, so that if there is going to be a serious impact, measures can be taken to keep people safe.”
UH rapid tracking
The FTN’s ability to quickly track fast-moving objects was key to the asteroid’s observation. The UH-operated telescope Pan-STARRS1, also based on Haleakalā, is the world leader in identifying large Near-Earth Objects. When potential threats are detected, telescopes on Maunakea will stop what they are working on and track the object to determine if it is a possible threat to Earth. Asteroid Terrestrial-impact Last Alert System or ATLAS, another UH-operated system, provides warnings for potentially city-destroying asteroids with up to a day’s notice and can identify regional-scale threats weeks in advance.
According to Micheli, tracking small asteroids ahead of potentially destructive ones is a good way to test preparedness.
“Our ability to detect them in space, quickly identify their impact trajectory, and track them until they hit our planet is an excellent way to demonstrate the effectiveness of our planetary defense systems,” said Micheli.
UH astronomers and Hawaiʻi’s world-class telescopes remain at the forefront of efforts to protect Earth from asteroid impacts.
