Asteroid 2024 YR4 may have spared Earth, but it’s not out of the headlines yet. New data suggests the 200-foot-wide rock has a 4% chance of slamming into the Moon in 2032—an event that could still send shockwaves through Earth’s satellite systems.
According to University of Western Ontario astronomer Paul Wiegert, the lunar impact could eject up to 100 million kilograms of debris into space—some of which could reach Earth’s orbit and damage satellites. Even astronauts on the Moon, if present, would be at risk.
“A 2024 YR4 impact on the Moon wouldn’t hurt anyone on Earth, but it could threaten space-based infrastructure,” Wiegert told Space.com.
A Blast Bigger Than Hiroshima
If 2024 YR4 strikes, the impact would be the largest lunar collision in 5,000 years, releasing energy equal to six million tons of TNT—roughly 400 times the power of the Hiroshima bomb.
“It would create a crater about one kilometer wide,” Wiegert added.
Most debris would fall back onto the Moon, but a small fraction—around 0.02% to 0.2%—could escape, traveling at 22,400 mph, or 11 times faster than a rifle bullet.
Space Weather Disruption and Meteor Shower?
While Earth’s atmosphere would vaporize most incoming debris, our satellites are exposed. Communication systems, GPS, and weather monitoring tools could all be affected by fast-moving lunar shrapnel.
And while the risk to people on the ground is negligible, we might still get a show: the impact could trigger a brief, intense meteor shower, visible to skywatchers with binoculars or small telescopes.
“It all depends on where on the Moon the asteroid hits,” Wiegert said. “Some regions could send much more debris toward Earth.”
Why There’s No “Lunar Torino Scale”
Could we create a new impact hazard scale for lunar collisions? Probably not, according to Richard Binzel, creator of the Torino Scale.
“Indirect consequences are too complex to categorize into one scale,” he explained. “It’s all about probability. Either an asteroid hits or it misses.”
So, Will It Hit?
We won’t know for sure until 2028, when YR4 becomes visible again. Until then, scientists estimate a 4% chance of impact—enough to be watched closely, but not enough to panic.
Wiegert’s team has submitted their findings to the American Astronomical Society and released a preprint on arXiv for early access.
As for now, all eyes are on 2028.
“We just need the data,” Wiegert said. “After that, we’ll know whether it’s a hit—or just another close call.”