A lunar impact could eject 100 million kilograms of debris—enough to trigger a meteor storm and damage orbiting satellites.
The asteroid 2024 YR4, once feared to be on a collision course with Earth, may now be targeting the moon, scientists say.
Discovered in late 2024, the 60-meter-wide space rock reached peak impact odds of 3.1% in February—making it the riskiest asteroid ever observed at the time.
Thanks to new observations, astronomers have ruled out an Earth impact. But YR4’s revised orbit now reveals a 4.3% chance of striking the moon on December 22, 2032.
“Size equals energy,” said Julien de Wit, a planetary scientist at MIT. A moon impact would be the largest in 5,000 years, potentially ejecting 100 million kilograms of lunar debris—some of which could reach Earth and threaten satellites.
While no danger to humans on Earth is expected, even millimeter-sized fragments traveling at extreme speeds could damage communications infrastructure in orbit.
“This could cause 10 years’ worth of satellite wear in just a few days,” said researcher Paul Wiegert.
If it occurs, the impact could produce a crater visible from Earth, spark a meteor storm, and offer scientists rare data on lunar impacts—unless, Wiegert added, future deflection missions change the outcome.