In the spring of 2024, the Moon received a visitor it could not refuse — a comet or asteroid the size of a city building, striking with enough force to carve a 222-metre wound into the lunar surface. It took humanity two years to notice, but when NASA researcher Robert Wagner finally spotted the bright scar in orbital imagery, the find carried unusual weight: such an impact occurs perhaps once a century, making this a rare chance to study cosmic violence while the evidence is still fresh. Named McGetchin, the crater now stands as both the largest newly discovered impact site in the solar syste
NASA discovers 'once in a century' Moon crater formed by spring 2024 impact
Objects arrive at full speed and leave their mark unfiltered
Mark
So NASA found a crater on the Moon. Why does that matter? There are thousands of craters up there.
Mimi
True, but this one formed recently—spring 2024—and we caught it early. Most craters we study are ancient. This one is fresh.
Luke
How do we know it formed in spring 2024 specifically? Did someone see it happen?
Mimi
No, not directly. The impact happened, but it wasn't detected until Robert Wagner spotted it in orbital imagery in 2026. The timing is inferred from when it wasn't there before.
Mark
And the size—222 metres—that's enormous, right?
Mimi
For a new crater, yes. The object that made it was the size of a building, three to six storeys tall. Scientists say impacts this big happen maybe once a century on the Moon.
Luke
Once a century—is that a precise estimate or a rough guess?
Mimi
It's an estimate. NASA states it that way in their blog post. The actual frequency could vary. But the point is they're rare enough that we don't see them often.
Mark
And this is the largest new crater ever found in the solar system?
Mimi
According to the Science Advances study, yes. Largest new one. There are bigger craters elsewhere, but none formed more recently that we know of.
Luke
Why does that distinction matter—new versus old?
Mimi
Because studying how a crater forms, while the evidence is still readable, teaches us about the Moon's geology. That knowledge helps prepare for the crewed missions coming soon.
Mark
From the US and China?
Mimi
Both are planning to send people to the Moon. Understanding the surface—how it fractures, how it responds to impact—is practical information for astronauts.
Le Pouls
- A building-sized object struck the Moon in spring 2024, carving a crater 222 metres wide — an event so rare it may not happen again for a hundred years or more.
- The impact went undetected for nearly two years, only surfacing when NASA's Lunar Reconnaissance Orbiter captured the telltale bright spot and dark halo in fresh orbital imagery.
- Scientists confirmed in a peer-reviewed study that McGetchin is the largest new crater ever identified anywhere in the solar system, raising the stakes of what this discovery means for planetary science.
- With no atmosphere to erode it, the crater will remain a pristine record of the impact — offering researchers a rare near-real-time window into how the lunar surface fractures and responds to force.
- Both the US and China are planning crewed Moon missions, and understanding fresh impact dynamics is no longer purely academic — it is preparation for the safety of future astronauts.
In the spring of 2024, the Moon received a visitor it could not refuse — a comet or asteroid the size of a city building, striking with enough force to carve a 222-metre wound into the lunar surface. It took humanity two years to notice, but when NASA researcher Robert Wagner finally spotted the bright scar in orbital imagery, the find carried unusual weight: such an impact occurs perhaps once a century, making this a rare chance to study cosmic violence while the evidence is still fresh. Named McGetchin, the crater now stands as both the largest newly discovered impact site in the solar system and a quiet reminder that the universe continues to reshape even our closest neighbor.
In spring 2024, a comet or asteroid roughly the size of a three-to-six-storey building slammed into the Moon, leaving a crater 222 metres across. No one noticed immediately. It was not until 2026 that NASA researcher Robert Wagner, reviewing imagery from the Lunar Reconnaissance Orbiter, spotted the distinctive bright spot ringed by a dark halo. NASA named it McGetchin.
The significance lies less in the crater's size — the Moon hosts far larger ancient scars — than in the rarity of witnessing one form. Scientists estimate an impact of this scale occurs perhaps once a century. A study in Science Advances confirmed McGetchin as the largest newly discovered crater anywhere in the solar system, and its freshness is precisely what makes it valuable: researchers can study crater formation as a near-live event rather than piecing together ancient geology.
The Moon's lack of atmosphere amplifies this value. Without air to slow or burn incoming debris, objects arrive at full speed and leave unfiltered marks that persist unchanged for vast stretches of time. McGetchin will remain largely as it is now — a preserved record of a single violent moment.
That preservation has practical implications. With the United States and China both planning crewed lunar missions in the coming years, understanding how the surface fractures, displaces material, and changes under impact is knowledge with real stakes for astronauts. McGetchin is not merely a scientific curiosity — it is a lesson the Moon has offered at an opportune moment.
In spring 2024, something massive struck the Moon. A comet or asteroid—roughly the size of a three-to-six-storey building—slammed into the lunar surface and left behind a crater 222 metres across. NASA researchers did not notice it right away. It took until 2026 for Robert Wagner, working with NASA's Lunar Reconnaissance Orbiter, to spot the scar in fresh orbital imagery. The crater appeared as a bright spot ringed by a dark halo, unmistakable once you knew to look for it. NASA named it McGetchin.
What makes this discovery significant is not the crater itself—the Moon is pocked with them, many far larger than McGetchin. What matters is the rarity of witnessing one form. Scientists estimate that an impact of this magnitude happens on the Moon roughly once every century, or even less frequently than that. The last time something this large struck was long enough ago that no one alive had seen it happen. This one did, and now researchers have a chance to study it while the evidence is still fresh.
A study published in Science Advances confirmed that McGetchin is the largest new crater ever discovered anywhere in the solar system. The distinction matters because understanding how craters form—watching the process unfold in near-real time rather than studying ancient scars—builds knowledge about the Moon's geology. Every impact tells a story about the lunar surface: what it is made of, how it responds to force, how it changes over time.
The Moon's lack of atmosphere makes this process visible in ways Earth's surface is not. Here, space debris burns up or slows down as it falls through air. On the Moon, there is nothing to stop it. Objects arrive at full speed and leave their mark unfiltered. That same absence of atmosphere means the crater McGetchin created will remain largely unchanged, a preserved record of the moment of impact.
Both the United States and China are planning crewed missions to the Moon in the coming years. Understanding how the lunar surface behaves when struck—how it fractures, how material is displaced, what hazards might emerge—is practical knowledge for astronauts who will land there. A crater this fresh, studied while the impact's effects are still legible, offers a window into conditions future explorers will face. The discovery, then, is not just a scientific curiosity. It is a piece of preparation for the next chapter of human presence on the Moon.
Citations marquantes
Scientists estimate that an impact of this magnitude happens on the Moon about once in a century or even longer— NASA
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