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A new scientific study suggests that a building-sized asteroid, named 2024 YR4, has a small but real chance of striking the Moon in 2032. If this collision happens, it would create a brilliant flash of light visible from Earth and trigger significant meteor storms. This space rock measures approximately 200 feet, or 60 meters, across. It was first discovered in late December 2024.
The building-size asteroid 2024 YR4 has a small chance of striking the moon in 2032 — and a new study predicts it could also put on a spectacular show for skywatchers by creating thousands of impact flashes as well as extreme meteor storms.
In early 2025, the asteroid caused a global stir. Initial calculations suggested it had the highest probability ever recorded for an asteroid of its size to collide with Earth, with odds reaching 3.1 percent. However, after scientists conducted more detailed observations and analyzed the asteroid's path, they definitively ruled out any impact with our planet during its close approach on December 22, 2032. Despite this safety confirmation, the possibility of the asteroid hitting the Moon captured the attention of the scientific community.
Yifei Jiao, a postdoctoral researcher at the University of California, Santa Cruz, found this scenario particularly interesting. He and his colleagues recognized it as a unique scientific opportunity. In an email to Live Science, Jiao explained that this event presents a rare "natural experiment." He noted that a forecastable impact by a small body could provide signatures that are both scientifically rich and operationally relevant. Motivated by this potential, the research team set out to thoroughly assess all plausible outcomes from a potential collision with the lunar surface.
To investigate the potential risks and effects, scientists built complex computer models of our solar system. These models included the asteroid, all major planets, Earth's Moon, and the Sun. They used these models to simulate the path of 2024 YR4 as it travels through the inner solar system. By slightly adjusting the asteroid's starting trajectory in each run, the team created 10,000 distinct simulations. These digital experiments allowed them to map the most likely areas for a collision on the Moon's surface.
Building on this work, the researchers performed another set of finer-scale simulations. These focused on modeling the physical impact process itself over a 500-second interval. They also tracked the potential debris field, following the paths of any lunar material that might be ejected with enough force to escape the Moon's gravity. The results of these simulations, which have been posted to the arXiv preprint server and await formal peer review, indicate that if an impact occurs, it will most likely happen along a corridor roughly 1,900 miles, or 3,000 kilometers, long on the Moon. This predicted impact zone lies just north of the prominent Tycho crater. For observers on Earth in the Northern Hemisphere, this location would appear in the Moon's lower half.
One of the most dramatic predicted effects is a brilliant flash of light at the moment of impact. The study's first author, Yifan He, a researcher at Tsinghua University in China, stated that the flash would be starlike. It could reach a brightness between magnitude -2.5 and -3. In the night sky, this would make it approximately as bright as the planet Venus. While the main flash is predicted to last between 200 and 300 seconds, or three to five minutes, He noted it would be reliably visible to the naked eye for at least 10 seconds when the flash is bright enough above background conditions.
If the collision happens, the predicted impact time is 10:19 a.m. Eastern Standard Time, or 15:19 Coordinated Universal Time. This timing means the flash would only be visible from parts of the world where the Moon is above the horizon at that moment. Prime viewing locations would include East Asia, Oceania, Hawaii, and western North America. However, there is a significant viewing condition. On the forecasted impact date, about 70 percent of the Moon's Earth-facing side will be illuminated by sunlight. For the main impact flash to be visible to an unaided eye, the asteroid must strike the Moon's darkened, unlit region. He and the study's second author, Yixuan Wu, also of Tsinghua University, have calculated that if the asteroid does hit the Moon, the probability of it striking this dark portion is only about 2.85 percent.
Even if the main flash occurs on the Moon's bright side, amateur astronomers using telescopes would still be able to detect it. The event would also likely produce other spectacles. The force of the primary impact would throw countless lunar rocks high above the surface. As these rocks rained back down, they would create potentially several thousand smaller secondary impact flashes across the Moon. These subsequent flashes, however, would be far dimmer than the initial explosion and would be extremely difficult to see without optical aid.
Furthermore, the study predicts that the impact could eject an enormous amount of material toward Earth. This could include up to 220 million pounds, or 100 million kilograms, of lunar rocks and dust. This ejected debris would enter Earth's atmosphere over the following weeks and months. Yixuan Wu describes the result as "super meteor storms," or extreme meteor showers that would be most prominent between two and 100 days after the lunar impact.
The probability of 2024 YR4 actually hitting the Moon remains fairly low and uncertain. Despite this, the very possibility excites scientists. Wu expressed enthusiasm about the potential for discovery. He told Live Science that such an event would represent a milestone for planetary science. It would turn the Earth-Moon system into a grand stage for validating our understanding of asteroid impacts and the physics of high-speed collisions.
While Earth is confirmed to be safe from 2024 YR4, the asteroid's journey has already provided invaluable experience for planetary defense. When it was first discovered and identified as a potential risk, telescopes around the world, including the powerful James Webb Space Telescope, quickly turned to observe it. These rapid and coordinated observations allowed astronomers to precisely refine their calculations of the asteroid's size and trajectory, ultimately confirming it would miss our planet.
This global response offers critical practice for humanity. As the study and tracking of 2024 YR4 demonstrates, the more proficient we become at detecting, tracking, and characterizing near-Earth objects, the better prepared we will be if a genuine, imminent threat from space ever emerges. The careful analysis of this asteroid, even one that poses no danger to Earth, helps scientists build the tools and knowledge needed to protect our future. The study of this event transforms a minor celestial risk into a major educational moment for the entire scientific community, proving that even small rocks in space can teach us profound lessons about our own planet's safety and our place in the solar system.