Although the risk of impact is low, some experts point out that the Moon could be the salvation of the Earth.
Asteroid 2024 YR4, discovered in December by a telescope in Chile, has become one of the most relevant astronomical topics in recent weeks.
The chances of it impacting the Earth on December 22, 2032, according to NASA, are around 2.2%, which means that there is a 1 in 45 chance of this happening, a significant increase from the initial 1.2%.
A low risk, but not zero
Despite the concerns, experts agree that the overall risk is still low. With more detailed observations, this possibility could be reduced to zero.
However, the threat must be taken seriously and, for this reason, a global network of centers dedicated to planetary protection was recently activated.
However, a new scenario has appeared in the equation that could change the course of events: asteroid 2024 YR4 might not impact the Earth, but it could impact the Moon.
The lunar impact: an unexpected twist
In an unexpected revelation, scientists have calculated that, in a remote but statistically possible scenario, the asteroid could impact the Moon.
According to David Rankin, operations engineer for the Catalina Sky Survey at the University of Arizona, there is a 0.3% chance of this happening. Although the possibility is low, it is still an option that is on the table.
The asteroid, with a speed of 48,000 kilometers per hour and a diameter of approximately 55 meters, would not represent a global threat.
Its size is comparable to Walt Disney World’s Cinderella Castle, or as long as the Leaning Tower of Pisa. An impact on Earth would be devastating on a local level, releasing an energy equivalent to more than 500 times the Hiroshima bomb.
Simulations by amateur astronomer Tony Dunn have shown that the impact corridor could pass through large cities such as Bogotá (Colombia), Lagos (Nigeria) and Mumbai (India).
What if it hits the Moon?
If the asteroid were to hit the Moon, it would create a crater up to 2 kilometers in diameter. According to Gareth Collins, professor of planetary sciences at Imperial College London, “we would be quite safe on Earth” as any ejected material would burn up in the atmosphere. However, the spectacle could be impressive.
Experts at the Northolt Branch Observatory in London suggest that the lunar impact could generate a flash brighter than a full moon, visible to the naked eye from Earth.
The area of possible impact would extend from the south of the Mare Crisium to the Tycho crater, located on the visible side of the Moon.
To obtain more precise data, the James Webb Space Telescope will observe the asteroid in March, before it disappears from our view until 2028. Although the current observations have been made with ground-based telescopes, these are less accurate than the heat measurements that will be made with Webb.
Scientific reassurance: “You don’t have to worry about anything”
Despite the attention that asteroid 2024 YR4 has attracted, scientists are keeping calm. Larry Denneau, senior software engineer for the asteroid impact warning system at the University of Hawaii, who was the first to spot the asteroid, says: “You have nothing to worry about. It’s a curiosity.”
In the same vein, Paul Chodas, director of NASA’s Center for Near-Earth Object Studies, insists that it is normal for the probability to fluctuate at first and that it is most likely to decrease with better observational data.
In fact, there is a 97.8% chance that the asteroid will not impact the Earth. Scientists hope that this figure will be reduced to zero as more data is collected.
History supports this optimism: in 2021, for example, NASA ruled out the possibility of the asteroid Apophis impacting in 2068 after new observations.
In short, although the threat of the YR4 asteroid deserves our attention, experts say there is no cause for alarm.
Science will continue to monitor the object and, over time, the probability of impact is likely to decrease to zero, leaving the Moon as Earth’s possible “lifeline”.
