Between April 11 and May 22, 2024, a space rock roughly the size of a three-to-six-story building slammed into the eastern limb of the Moon, creating a 222-meter-wide and 43-meter-deep formation named the McGetchin crater. Identified by researchers using NASA’s Lunar Reconnaissance Orbiter, this stands as the largest newly formed impact crater discovered since human monitoring began.
Detecting a Once-in-a-Lifetime Lunar Impact
Finding a fresh scar on a planetary body that lacks a protective atmosphere requires methodical data analysis. The Moon’s surface has accumulated countless craters over billions of years, making new additions difficult to spot without high-resolution orbital imaging. However, a spacecraft that has been circling the lunar environment for over 17 years changed that equation.
According to research published on October 16 in the journal Science Advances, crater production models indicate that an impact of this magnitude happens roughly once every 132 years. That statistical rarity makes the event a once-in-a-lifetime observation for planetary scientists. The research team named the site the McGetchin crater in honor of Dr. Thomas McGetchin, an Apollo-era lunar scientist who advanced the study of impact mechanics.
Before this discovery, the largest contemporary impact crater identified on the Moon measured an estimated 70 meters in diameter. The McGetchin formation easily surpasses that metric at 222 meters wide—spanning slightly more than the length of two football fields—and plunges 43 meters deep, which is deep enough to stack three school buses vertically.
How the Lunar Reconnaissance Orbiter Spotlit the Scar
Operated by NASA and utilizing seven onboard instruments, the Lunar Reconnaissance Orbiter (LRO) maps the Moon’s temperature, surface composition, topography, and radiation from a polar orbit. Robert Wagner, an image-processing specialist at Intuitive Machines who works with the Lunar Reconnaissance Orbiter Camera data, first spotted the McGetchin crater on October 24, 2025. He was reviewing overlapping before-and-after images that highlight anomalously dark or bright surface variations.
“I simply stopped, larguei tudo e comecei a investigar o que era aquele ponto,” Wagner stated, noting that it displayed the clearest impact debris pattern he had ever seen in such imagery. Software used by LRO team members flags any alterations tied to illumination or shadows, requiring researchers to manually weed out false positives from real geological shifts. Once flagged, the Narrow-Angle Camera captured high-resolution close-ups that allowed the team to measure the exact geometry of the crater and its surrounding terrain.
The Thermal Signature of a Lunar “Cold Spot”
The impact did more than carve out a massive basin; it also altered the thermal properties of the surrounding regolith. A separate group of researchers analyzed data from the LRO Diviner instrument, uncovering a 6.4-kilometer-wide zone encircling the crater that registered roughly 8.9 degrees Celsius cooler during the lunar night than adjacent terrain.
"Their large extent indicates that impacts can modify the surface much further than the crater itself. We were very lucky that it formed during the lifetime of the LRO mission and we were able to observe the region both before and after the impact."
Researchers attribute these cold spots to physical disruptions in the top layer of dust and rock, creating a looser material matrix with a reduced capacity for retaining heat through the lunar night. Mark Robinson, principal investigator for the Lunar Reconnaissance Orbiter Camera at Intuitive Machines, emphasized that tracking these surface modifications provides vital baseline data on how asteroids fragment and how frequently they strike rocky bodies.
Implications for Future Lunar Infrastructure and Artemis Planning
Understanding the frequency and scale of modern impacts is not purely academic. As NASA’s Artemis program and international space agencies lay the groundwork for long-term human exploration and permanent surface bases, infrastructure must be engineered to withstand ongoing bombardment.
He noted that the object likely matched the scale of the Chelyabinsk meteor that exploded over Russia in 2013. That 17-to-20-meter asteroid released energy equivalent to dozens of Hiroshima-class atomic bombs, shattering glass across thousands of buildings.
“If something like that crossed our atmosphere and hit the surface of the Earth, not catastrophic, but we certainly would notice,” Andrews-Hanna noted. “These events serve to remind us of how vulnerable we are, and of how important it is to catalog and track near-Earth asteroids that could potentially hit our planet.”
