Odds of asteroid 2024 YR4 hitting the Moon go up again
New observations by NASA's powerful James Webb Space Telescope helped scientists increase the impact probability to 4.3%. Still, there is a more than 95% chance asteroid 2024 YR4 doesn't hit the Moon on Dec. 22, 2032.
What are the chances asteroid 2024 YR4 will hit Earth?
A NASA asteroid tracker explains how scientists are calculating the risk to Earth from asteroid 2024 YR4.
An asteroid that, until a few months ago, was believed to be a threat to Earth is increasingly looking like it could crash into the Moon in 2032.
Asteroid 2024 YR4 was discovered on Dec. 27 by the Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in Río Hurtado, Chile. Since its discovery, the asteroid has warranted international attention, jumping to the highest asteroid threat on the Torino Impact Hazard Scale.
CHANCES ASTEROID 2024 YR4 WILL HIT MOON INCREASE BUT EARTH REMAINS IN THE CLEAR
In February, new ground-based observations dropped those chances of an Earth impact enough that asteroid 2024 YR4 is no longer considered a threat to Earth. The international astronomy community continues to closely watch asteroid 2024 YR4, which is no longer visible through ground-based telescopes until 2028.
On March 26, 2025, NASA’s James Webb Space Telescope captured images of asteroid 2024 YR4 that indicate the asteroid is about the size of a 15-story building. Researchers also say the asteroid’s surface may be dominated by rocks that are maybe fist-sized or larger. Asteroid 2024 YR4 is smallest object targeted by Webb to date.
(NASA, ESA, CSA, STScI, Andy Rivkin (APL) / NASA)
In May, a team led by Andy Rivkin, with Johns Hopkins Applied Physics Laboratory in Maryland, used the James Webb Space Telescope's (JWST) Near-Infrared Camera to hone in on 2024 YR4. JWST data, along with expert analysis from NASA's Center for Near-Earth Object Studies, have refined the asteroid's orbit, increasing the chances of a crash with the Moon on Dec. 22, 2032, from 3.8% to 4.3%. In February, the odds of a Moon impact were about 1.7%.
The range of possible locations – represented by yellow points – of 2024 YR4 on Dec. 22, 2032. The range decreases from April to June as we gained more data and improved our certainty of the asteroid’s position. Earth is close to the center of the white circle, which represents the Moon’s orbital path.
(NASA/JPL Center for Near-Earth Object Studies)
However, NASA said if the asteroid does collide with the Moon, it will not alter its orbit. The Moon is covered in crater impacts from other space collisions.
Previous observations by JWST helped determine 2024 YR4 is about 200 feet wide, or about the height of a 15-story building, Rivkin wrote in an April blog post for NASA.
Asteroid 2024 YR4 has dipped behind the Sun and beyond Webb's view for now.