Scientists are closely monitoring a sizable asteroid known as “2024 YR4,” which initially posed a potential threat to Earth. Although recent analyses indicate that the asteroid no longer represents a significant risk for an Earth impact in December 2032, its chances of colliding with the moon have increased to 4.3%. While this probability is still low, a collision with the moon could lead to interesting consequences for both lunar and terrestrial environments.
Initially discovered in December 2024, 2024 YR4 drew attention due to its potential risk of impacting Earth, with a 3% chance reported at the time. Measuring roughly 200 feet in diameter—comparable to a 10-story building—this near-Earth asteroid earned the nickname “city killer” owing to the extensive damage it could cause if it were to strike our planet.
If 2024 YR4 were to strike the moon, experts anticipate an impact at speeds tens of thousands of miles per hour. This violent collision would create a considerable crater and scatter moon debris into space. Despite the low likelihood of Earth being directly affected by such rock fragments, there are concerns for astronauts and satellites in nearby orbits, including those essential for GPS, cell communications, and weather predictions.
Importantly, NASA has plans to decommission the International Space Station in 2031, well before the asteroid’s potential impact.
Interestingly, should 2024 YR4 collide with the moon, it is theorized that observers on Earth could witness the explosion, as the asteroid is predicted to impact the near side of the moon—the side facing us. Dr. Paul Wiegert from Western University highlighted that this event would mark the largest asteroid impact on the moon in approximately 5,000 years. With the right equipment, such as simple telescopes or binoculars, viewers could catch this extraordinary spectacle. Additionally, any debris ejected into space could lead to a spectacular meteor shower observable shortly after the event.
As it currently stands, 2024 YR4 is not observable with ground-based telescopes, as it remains distant in its orbit around the sun. However, NASA is optimistic about gathering more data when it returns to a closer orbit around Earth in 2028.
Overall, while the situation regarding asteroid 2024 YR4 poses some risks, astronomers view any potential lunar impact with excitement, as it represents a unique opportunity for scientific observation and public engagement with space exploration.