Leonard David's INSIDE OUTER SPACE

The current impact corridor for 2024 YR4 (yellow) projected on a map of the Moon’s near side from Lunar
Reconnaissance Orbiter (E. J. Speyerer et al. 

Is it likely that in 2032 Earth’s Moon is going to be on the receiving end of an asteroid?

According to an international team of researchers, there’s a 4 percent chance of the space rock hitting the Moon. If so, the rebound of repercussions on the lunar landscape, cis-lunar space, as well as Earth-circling satellites appears worrisome.

The cosmic culprit is the nearly 200 feet (60 meters) in diameter asteroid 2024 YR4.

Odds are?

Earlier this month, NASA updated YR4’s lunar impact odds, noting that the James Webb Space Telescope focused in on the space rock before it escaped from view in its orbit around the Sun. 

With the additional data, experts from NASA’s Center for Near-Earth Object Studies at the agency’s Jet Propulsion Laboratory in Southern California further refined the asteroid’s orbit.

“The Webb data improved our knowledge of where the asteroid will be on Dec. 22, 2032, by nearly 20%, the NASA posting explains. “As a result, the asteroid’s probability of impacting the Moon has slightly increased from 3.8% to 4.3%.”

Image credit: NASA

In a spurt of reassurance the NASA post adds that “in the small chance that the asteroid were to impact, it would not alter the Moon’s orbit.”  

Consequences for Earth

But the consequences from such an impact have been highlighted in work led by Paul Wiegert of the Department of Physics and Astronomy at the University of Western Ontario, London, Canada.

This study was supported in part by the NASA Meteoroid Environment Office.

“If 2024 YR4 strikes the Moon in 2032, it will (statistically speaking) be the largest impact in approximately 5000 years,” the research team reports.

Such a hit to the Moon would release 6.5 megatons of TNT equivalent energy and produce a roughly one kilometer crater.

Wiegert and colleagues estimate that up to 108 kilograms of lunar material could be “liberated” in such an impact by exceeding lunar escape speed. “Depending on the actual impact location on the Moon as much as 10% of this material may accrete to the Earth on timescales of a few days,” they report.

Captured by astronaut Don Pettit aboard the International Space Station (ISS), this long-exposure photograph showcases Earth’s city lights, the upper atmosphere’s airglow, and streaked stars. The bright flashes at the center are reflections of sunlight from SpaceX’s Starlink satellites in low-Earth orbit.
Image credit: NASA

Eye-catching

The incoming ejecta could cripple satellites in near-Earth space late in 2032.

It becomes possible that “hundreds to thousands of impacts from mm-sized debris ejected by a lunar impact from 2024 YR4 will be experienced across the entire satellite fleet,” the researchers observe. “Such impacts may damage satellites, but are small enough to generally not end active missions or cause breakups,” they add.

The resulting meteor shower at Earth “could be eye-catching,” the research paper suggests.

NASA’s Artemis program wants to establish a sustainable presence on the Moon.
Image credit: NASA

Moreover, the ejection of material from the Moon could be a serious hazard to lunar-circuiting spacecraft, such as the projected Lunar Gateway. The impact would “likely pose even greater dangers to any lunar surface operations given that most ejecta mass will accumulate across a wide swath of the Moon, Wiegert and colleagues note.

Planetary defense

The travel time from the hit on the Moon to Earth is typically several days “but does depend on the precise location of the impact if it even occurs, which probably cannot be determined until the asteroid returns to visibility in 2028.”

Wiegert and colleagues conclude: “Our analysis highlights that issues of planetary defense extend beyond just the effects of impacts on Earth’s surface. Impacts on the Moon may generate particles which can interfere with low Earth orbiting satellites.”

To read the paper – “The Potential Danger to Satellites due to Ejecta from a 2032 Lunar Impact by Asteroid 2024 YR4” – at:

https://arxiv.org/pdf/2506.11217