Using data from NASA’s James Webb Space Telescope observations collected on February 18 and 26, experts at NASA’s Near-Earth Object Studies Center at the agency’s Jet Propulsion Laboratory in Southern California have refined the orbit of near-Earth asteroid 2024 YR4 and ruled out the possibility of a lunar impact on December 22, 2032. With the new data, it is expected that 2024 YR4 passes by the lunar surface at a distance. of 13,200 miles (21,200 km).
This update reflects greater precision in our understanding of where the asteroid is expected to be in 2032 rather than a change in its orbital path. Previous analyses, conducted before the addition of these new observations, suggested that 2024 YR4 had a 4.3% chance of a lunar impact on this date.
The observing team, led by the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, used Webb to capture the two additional observations of 2024 YR4 in an application of the telescope’s unique capabilities. Since spring 2025, the asteroid has not been observable from ground- or space-based observatories, except for this use of Webb to make one of the faintest observations of an asteroid ever made.
Asteroid 2024 YR4 was discovered in late 2024 by the NASA-funded Asteroid Land Impact Last Alert System station in Chile. In early 2025, available information on the asteroid’s trajectory indicated that it had a small but notable chance of impacting Earth. Over time, with more observations collected by observatories around the world, NASA concluded that the object does not pose a significant impact risk to Earth on December 22, 2032 or during the next century. It is typical to update initial observations and risk models once additional observational data are collected and the models can be refined.
