An asteroid struck the Moon on 4 March 2025 and created a new crater about 54 metres wide. NASA’s Lunar Reconnaissance Orbiter confirmed the impact. The event is the first observable lunar impact of this size in more than a century.
The impact occurred on the lunar near side. NASA reported the detection in March 2025. AP News and NASA Science published confirmation shortly after.
What asteroid hit the moon and when did it happen
The impactor was an asteroid roughly 40 to 50 metres across. That is comparable to a six-storey building. The object entered the lunar surface at high velocity.
Detection was made by the Lunar Reconnaissance Orbiter Camera, LROC. Before and after images show the new crater formation clearly.
How big was the asteroid and how large is the new crater
The asteroid was estimated at ~40-50 metres. The crater is about 54 metres in diameter. Impact energy was sufficient to excavate lunar regolith and eject debris.
LROC images provided the measurement. The crater is fresh. It shows bright rays from ejected material.
Why NASA calls it a once-in-a-lifetime and once-in-century event
NASA describes the event as once-in-a-century for observable impacts. Large, visible lunar impacts are rare. The last comparable confirmed event dates back more than 100 years.
The term once-in-a-lifetime refers to the opportunity to capture before and after images from orbit. Such imaging is uncommon.
How NASA’s Moon Orbiter spotted the new crater and what technology was used
The Lunar Reconnaissance Orbiter has orbited the Moon since 2009. LROC provides high-resolution imaging at ~0.5 metres per pixel.
NASA compared images taken before 4 March 2025 with images taken after. The new crater appeared in the later image. The change was verified by the Lunar Reconnaissance Orbiter team.
What this discovery means for planetary defense and future lunar missions
The impact demonstrates the value of continuous lunar monitoring. It helps refine impact flux models for near-Earth asteroids.
Data supports planetary defense monitoring. It informs risk assessment for Earth-bound asteroids.
The finding is relevant to the Artemis program. New craters affect landing site safety. Lunar geology understanding improves with each observed impact.
Summary of the once-in-century asteroid impact event
NASA confirmed a new lunar crater formed by asteroid impact. The event was detected by LRO. Media coverage included AP News and Sky News.
Key Facts at a Glance
| Parameter | Value |
|---|---|
| Asteroid size | ~40-50 metres, about a six-storey building |
| Crater size | ~54 metres diameter |
| Impact date | 4 March 2025 |
| Detection method | Lunar Reconnaissance Orbiter Camera LROC before/after imaging |
| Mission | NASA Lunar Reconnaissance Orbiter |
| Frequency | Observable impacts of this scale occur roughly once per century |
How the Discovery Was Made and Verified
NASA Science published details on the detection timeline. AP News reported confirmation. Independent media coverage followed.
Comparison with previous known lunar impact flashes shows consistency. The new crater adds to the catalog of observed impacts.
Why This Asteroid Impact Matters
The event provides direct data on impact mechanics. It improves models of crater formation on airless bodies.
Planetary defense benefits from better monitoring of near-Earth asteroids. Lunar impacts serve as a natural laboratory.
Artemis landing site selection requires up-to-date surface maps. Fresh craters change surface hazards.
What’s Next for Lunar Impact Monitoring
NASA continues monitoring with LRO. Ongoing programs track impact flashes and new craters.
The public can follow NASA Science updates. Impact monitoring data is released regularly.
💡 Frequently Asked Questions (FAQ)
- Q: What asteroid hit the Moon and when did it happen?
- A: A roughly 40-50 metre asteroid, comparable to a six-storey building, struck the Moon’s near side on 4 March 2025 at high velocity.
- Q: How big was the asteroid and how large is the new crater?
- A: The impactor was estimated at 40-50 metres across and formed a fresh crater about 54 metres in diameter with bright ejecta rays visible in LROC images.
- Q: Why does NASA call it a once-in-a-century and once-in-a-lifetime event?
- A: NASA describes it as once-in-a-century because large visible lunar impacts are rare, with the last comparable confirmed event over 100 years ago, and once-in-a-lifetime due to the rare before-and-after orbital imaging.
- Q: How did NASA’s Moon orbiter spot the new crater and what technology was used?
- A: NASA’s Lunar Reconnaissance Orbiter Camera captured before and after images of the impact site, clearly showing the new crater formation, size and ejected lunar regolith.
Extended Reading
NASA Science: NASA’s Moon Orbiter Spots New, ‘Once-in-Century’ Moon Crater. https://science.nasa.gov/solar-system/moon/nasas-moon-orbiter-spots-new-once-in-century-moon-crater/
AP News: Moon lunar crater space NASA. https://apnews.com/article/moon-lunar-crater-space-nasa-80eea242ad275fda1f7a88587cdccd2f
Sky News: Asteroid the size of six-storey building crashed into moon in once-in-a-lifetime moment, says NASA. https://news.sky.com/story/asteroid-the-size-of-six-storey-building-crashed-into-moon-in-once-in-a-lifetime-moment-says-nasa-13588849