Scientists have found a crater on the moon larger than the Roman Colosseum, resulting from a powerful impact that occurred two years ago, initially going unnoticed. This steep-sided hole measures 222 meters across and up to 43 meters deep, standing as the largest known impact crater in the solar system from recent times.
This significant event is estimated to happen only once every 132 years, providing valuable insights as NASA prepares for lunar base construction for astronauts. Researchers described this occurrence as a statistically rare observation in one of the two studies published in the journal Science Advances.
The Lunar Reconnaissance Orbiter (LRO) detected the crater on the moon’s near side in May 2024, following its formation by an asteroid or comet fragment. The impact evaded detection by Earth-based and space telescopes in real-time.
Named after Thomas McGetchin, a former director of Houston’s Lunar and Planetary Institute, the crater was identified by LRO’s wide-angle images in August 2025, with detailed pictures captured later and the discovery confirmed early this year.
The moon has been marked by ancient impact craters, with the latest impact stretching over 100 kilometers on the lunar surface. Mark Robinson, the chief scientist for LRO’s cameras at Intuitive Machines, noted that dust and rocky soil were ejected at a higher angle than anticipated.
A separate study highlighted a seven-kilometer-wide cold spot surrounding the new crater, indicating a disturbance in the moon’s topsoil. Co-author David Paige from the University of California, Los Angeles, likened these impacts to gardening, stirring up surface materials.
Robinson emphasized that the moon’s top two centimeters of soil are overturned every 80,000 years by ejected material, faster than previously believed. He dispelled the notion that Apollo moonwalkers’ footprints would endure forever, stating they would vanish within that timeframe.
Future steps involve assessing the risk of ejected crater material hitting NASA’s planned moon base to enhance structural resilience and mitigate potential damage concerns.
