What size asteroids can astronomers detect from Earth that could potentially pose a threat to our planet? This is what a recent study published in Nature hopes to address as an international team of researchers led by the Massachusetts Institute of Technology (MIT) investigated new methods for detecting asteroids as small as tens of meters across, known as “decameter” asteroids, that could leave the main asteroid belt that resides between Mars and Jupiter and potentially strike Earth, also called near-Earth objects (NEOs), or objects that come within 45 million kilometers (28 million miles) of Earth’s orbit.
For the study, the researchers used infrared data from NASA’s powerful James Webb Space Telescope (JWST) they collected studying exoplanets in the TRAPPIST-1 system to search for small-sized asteroids using computational methods that could scan thousands of images at once. In this case, the researchers scanned more than 10,000 images and initially discovered eight known asteroids within the main asteroid belt, with a second scan revealing 138 new asteroids only tens of meters in diameter. The icing on the cake was identifying that a few of the new asteroids could eventually become NEOs.
“We have been able to detect near-Earth objects down to 10 meters in size when they are really close to Earth,” said Dr. Artem Burdanov, who is a research scientist in MIT’s Department of Earth, Atmospheric and Planetary Sciences and lead author of the study. “We now have a way of spotting these small asteroids when they are much farther away, so we can do more precise orbital tracking, which is key for planetary defense.”
The field of planetary defense has become increasingly more important in the last few years with the goal of detecting and deflecting objects that could strike Earth, potentially resulting in catastrophic damage and loss of life. This was demonstrated with NASA’s Double Asteroid Redirection Test (DART) mission in 2022, resulting in impacting the asteroid Dimorphos and changing its orbit by 32 minutes.
How many more decameter asteroids will astronomers discover in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Nature, EurekAlert!, NASA
Featured Image: Artist's illustration of NASA's JWST identifying decameter asteroids in the main asteroid belt. (Credit: Ella Maru)
