The risk of impact of the 2024 YR4 asteroid with the earth has doubled, but the probability remain scarce. There is another unknown: a 0.3% of the possibility of hitting the moon.
We talked to you in the past few days of the asteroid 2024 YR4 which could hit our planet in 2032 3%, one however extremely remote possibility. “At the moment, there is still a probability of 97.9% of a lack of impact with the earth,” David Randkin, operational engineer of the Sky Survey Catalina of the University of Arizona, has reassured. «When the probability doubled from 1% to 2%, this caused a lot of noise. It is not the same as going from 40% to 80%, however. For this asteroid it is not worth losing sleep».
But it is not the only threat: new estimates reveal a small, but concrete, possibility that the target is instead the moon.
Worrying dimensions. This “spatial stone” measures about 55 meters in diameterroughly as much as the church of Sant’Ambrogio in Milan, and dart at a speed of 48,000 km/h. Although not able to extinct life on earth, 2024 YR4 could still sweep a big city, freeing an energy equal to 8 megatons, beyond 500 times higher than that released by the atomic bomb that razed to Hiroshima soil.
Unknown moon. Rankin has revealed on Bluesky that the asteroid also has a probability of 0.3% of hitting the moon. The consequences of such an impact would be visible from the earth, even if not directly dangerous for us.
“There is the possibility that the impact exposes the material that could affect the earth, but I strongly doubt that this could represent a serious threat,” said Randkin. However, the lunar impact would not pass unnoticed. Rankin has always estimated that a collision with the moon could release an energy equivalent to 340 Hiroshima bombs. “It would probably be very visible from the earth“, He said. Gareth Collins, professor of Planetary Sciences at Imperial College London, confirmed that if the asteroid were to hit the moon “we would be safe on earth», Adding that Any material expelled from the collision would disintegrate into the terrestrial atmosphere.
Small scar. During its existence, the moon was repeatedly affected by asteroids, as evidenced by its surface dotted with craters. However, an impact with 2024 YR4 would leave a crater of about 2 kilometers in width, a “small” scar if compared to the largest crater of the moon, the South-Aitken Polo Polo, which extends for over 2,400 km in diameter.
Despite The chances of impact with the earth or moon remain lowan international team of scientists has obtained the use of the James Webb (JWST) spatial telescope to study 2024 YR4 closely and will do it in the next few days. The astronomers, so far, have been able to observe the asteroid only by terrestrial telescopes, estimating its size according to the amount of reflected light, a rather inaccurate measurement. The JWST, on the other hand, will measure the heat emitted by the asteroid, providing a much clearer image of its size and the composition of the surface.
