The latest simulation shows that if the 60-meter diameter “city killer” asteroid 2024 YR4 were to collide with the Moon in 2032, it could eject a large amount of debris from the lunar surface, scattering towards Earth like “bullets,” causing a spectacular meteor shower and posing a threat to space infrastructure.
Since the discovery of this asteroid at the end of 2024, it was initially assessed to have a 3.1% chance of colliding with Earth in December 2032, prompting NASA to track it closely. Although subsequent studies have ruled out the possibility of a direct impact on Earth, scientists in April this year found that it could still collide with the Moon. According to the latest estimates in June, the probability of hitting the Moon has increased to 4.3%.
The latest research, led by space dynamics expert Paul Wiegert of Western University in Canada, was published on the arXiv platform of Cornell University on June 12. The team calculated that if the asteroid were to impact the Moon, it would eject approximately 100 million kilograms of debris. If it hits the side facing Earth, up to 10% of the debris could be attracted by Earth’s gravity, triggering a spectacular meteor shower visible globally for several days.
This impact could release energy comparable to a large nuclear explosion, becoming the largest celestial body collision with the Moon in the past 5,000 years. While there is no concern for ground safety, satellites and space stations could face significant risks. Simulations show that the probability of satellites being hit by debris would increase by a factor of 1,000. Wiegert warned that “a centimeter-sized pebble hitting at speeds of tens of thousands of meters per second is enough to destroy a satellite or space station.”
If the future risk of a lunar collision further escalates, the world may consider initiating deflection actions. In 2022, NASA successfully impacted the asteroid Dimorphos with the DART mission and altered its orbit, demonstrating intervention capability. Wiegert called 2024 YR4 an ideal test subject but also cautioned that if action is taken too late or hastily, it could inadvertently push it towards Earth, leading to a disaster.
Currently, the probability of the asteroid colliding with the Moon has risen to 4.3%, with the final fate expected to be determined when it approaches Earth again in 2028.
(Reference: Report by “Life Science”)