NASA’s Lunar Reconnaissance Orbiter has discovered the biggest, freshest impact crater ever seen in the solar system. Named McGetchin crater, the 728-foot-wide pockmark formed in the spring of 2024 and offers geologists a rare, pristine window into the moon’s shallow subsurface and impact history.
A Once-in-a-Century Impact on the Lunar Near Side
Since entering lunar orbit in 2009, NASA’s Lunar Reconnaissance Orbiter has captured more than 3 million images of the moon. Among those thousands of images, scientists identified a striking new arrival located about 330 kilometers from the edge of the Mare Crisium on the moon’s near side, as detailed in Universe Today. The impact created the McGetchin crater, measuring roughly 728 feet (222 meters) wide and 141 feet (43 meters) deep. Researchers note that a cavity of this scale is comparable to a hole spanning two American football fields and plunging deep enough to swallow a 14-story building.
The bolide responsible for the crater is estimated to have been the size of a three-to-six-story building. Because the solar system contains vastly more small debris than large objects, cataclysmic strikes of this magnitude are exceptionally rare. Live Science reported that researchers calculate an impact of this scale happens on the moon roughly once every 130 years.
The crater’s appearance in images from spring 2024 marks it as the largest fresh pockmark discovered since the orbiter began its mission, according to findings published in two papers in the journal Science Advances.
Unlocking the Geology of the Lunar Subsurface
Because the moon lacks liquid water and wind, its surface preserves impact scars for billions of years without the erasing effects of erosion and plate tectonics that characterize Earth. McGetchin crater sits directly on a geologic boundary between dark, flat volcanic mare deposits and the brighter, hillier ancient highlands crust. This unique positioning allowed the impact to excavate materials from both distinct zones, giving researchers a direct look at the strata beneath.
Erik Asphaug of the University of Arizona described the discovery as a treasure trove for understanding the immediate mechanics of deep excavation. Scientists analyzing data from the orbiter’s Diviner thermal instrument also discovered a four-mile-wide thermal anomaly surrounding the site. During the lunar night, this ring of disturbed soil is roughly 16 degrees Fahrenheit colder than the surrounding regolith.
The cold spot forms due to disturbance of the regolith around the crater.
This thermal signature forms because the impact decompacted and pulverized the upper layers of lunar dust and rock, creating a fluffy matrix incapable of holding daytime warmth. Similar cold spots associated with young craters can persist for up to two million years, serving as reliable markers for recent cosmic impacts across the lunar globe.
Implications for Future Artemis Landings and Seismicity
The dynamics of how impact energy travels through the lunar crust carry practical consequences for upcoming human exploration. As NASA advances its Artemis campaign to establish sustainable infrastructure near the lunar South Pole, researchers must account for both high-speed ejecta and internal seismic hazards.
Timothy Glotch of Stony Brook University noted that visible imagery reveals ejecta spraying for hundreds of crater radii beyond the rim, posing potential risks to exposed equipment and permanent outposts. Compounding these surface hazards, separate modeling published in the Planetary Science Journal indicates that the moon’s ongoing global contraction—driven by interior cooling and Earth’s tidal forces—generates young thrust faults and shallow moonquakes capable of producing strong ground shaking near the south polar region.
The study mapped specific scarps within candidate landing zones like the de Gerlache Rim 2, warning that even light seismic activity could trigger regolith landslides in permanently shadowed regions where vital resources like ice are trapped. As NASA noted, understanding these global seismic hazards will require expanding beyond legacy Apollo data through upcoming missions such as the Farside Seismic Suite.
Searching the Past and Preparing for the Next Era
Pinpointing the exact timing of the McGetchin impact required painstaking orbital comparisons. Because the spacecraft orbits the moon roughly 12 times a day and images only narrow strips on each pass, catching an impact without a visible flash relies on routine repeat imaging that spans years. The crater went unnoticed until researchers systematically compared historical frames with data pulled late last year.
Astronomers and skywatchers pore over archival footage from Earth, speculating that a impactor of that scale might have generated a visible flash from our planet if anyone happened to be looking at the right moment. Yet as researchers look toward the future of lunar science, questions remain about how long current monitoring capabilities can last.
