Amazing stuff!
"The new crater, named McGetchin, formed sometime between 11 April and 22 May 2024, when, unbeknownst to us, a comet or asteroid the size of a three-to-six-story building slammed into the Moon. The depression it left behind on the eastern side is two football fields long—a size only formed from collisions that occur once every 132 years, on average. Researchers found it by comparing images of large swaths of the lunar surface taken with the Wide-Angle Camera on NASA’s Lunar Reconnaissance Orbiter (LRO), then checking closer in with its Narrow-Angle Camera.
They soon realized that the crater wasn’t just impressive for its size, but for the effects it has had on its surroundings. LRO also observed that the 7-kilometer-wide area around the crater was about 8°C to 9°C cooler at night than the surrounding surface. Researchers think that the impact of the asteroid or comet stirred up nearby lunar dust, making it less dense and less effective at trapping heat. ..."
From the abstract (1):
"Observing the aftermath of recent impact events on the Moon tests models of impact frequency, surface change rates, and cratering physics.
The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC; 100-meter scale) images the whole Moon each month and has done so since 2010.
Comparing images from two months under similar lighting conditions enables automated detection of surface changes.
In fall 2025, a routine temporal comparison of WAC image sets revealed a new 222-meter-diameter crater that formed in spring 2024. This is the largest contemporary impact crater found in the Solar System and, according to current models, a once-in-132-year event.
Later, a series of LROC Narrow Angle Camera (NAC) images provided high-resolution (meter-scale) photometric and topographic information.
These images show that the crater exposed complex geology, inform current models of cratering mechanics, and document widespread surface changes extending more than 1000 crater radii."
A new 222-m diameter lunar crater (open access, 1)
New lunar crater reveals extensive distal regolith modification (open access, 2)
The crater site, before and after impact
Midnight temperature maps before and after impact reveal a ~7-km-wide “cold spot” around McGetchin crater.
Fig. 4. Key geomorphic features of McGetchin crater.
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