Scientists have identified a crater on the moon that surpasses the size of the Roman Colosseum, resulting from a significant impact that occurred two years ago, initially undetected. Measuring 222 meters across and up to 43 meters deep, this crater stands as the largest known recent impact crater in the solar system. Such a substantial event is estimated to occur approximately once every 132 years, providing valuable insights for NASA as they plan to establish a lunar base for astronauts.
“This occurrence is statistically rare, essentially a once-in-a-lifetime observation,” stated the researchers in one of two studies published in the journal Science Advances. The crater, named after the late Thomas McGetchin, was spotted by NASA’s Lunar Reconnaissance Orbiter (LRO) on the moon’s near side in May 2024, following a collision with an asteroid or comet fragment. Despite escaping detection by Earth-based and space telescopes in real-time, LRO’s wide-angle images revealed the crater in August 2025, with detailed pictures confirming the discovery in early 2026.
The impact, akin to gardening on the moon, stirred the lunar surface over 100 kilometers, ejecting dust and rocky soil at unexpected angles. Mark Robinson, chief scientist for LRO’s cameras at Intuitive Machines and lead author of one study, noted that the ejected material overturns the moon’s top two centimeters of soil every 80,000 years, faster than previously believed. This finding challenges the notion that the footprints left by Apollo moonwalkers will endure indefinitely, as Robinson highlighted they will likely disappear within this timeframe.
A cold spot spanning seven kilometers surrounding the crater was also identified in a separate study, indicating a loosening of the moon’s topsoil. Co-author David Paige of the University of California, Los Angeles, likened this phenomenon to gardening, reshuffling sediments and redistributing subsurface materials to the surface. This insight is crucial for understanding the risks of ejected crater material striking NASA’s planned lunar base, assisting engineers in fortifying structures against potential damage.