A newly discovered asteroid named 2024 YR4 is now considered the riskiest asteroid ever detected, according to NASA and the European Space Agency (ESA). Calculated odds of a collision with Earth in 2032 stand at 3.1% for NASA and 2.8% for the ESA.
The narrow difference lies in their methods for determining the asteroid’s orbit and modeling its potential impact. However, both organizations acknowledge that 2024 YR4 poses a significant threat to Earth. The asteroid’s diameter measures 350 meters (1,148 feet) and is currently ranked at a Torino Scale of 3, indicating a “current calculation gives a 1% or greater chance of collision capable of localized destruction.”
Scientists are optimistic that further observations will lead to re-assignment of the asteroid’s level. Binzel, the inventor of the Torino Scale, notes that as more data is gathered, the uncertainty region shrinks, and the impact probability may rise.
Astronomers are using multiple telescopes to study 2024 YR4 and understand its size and orbit. They expect the asteroid to pass harmlessly by Earth in 2028 and again in June of the same year. The James Webb Space Telescope will also be used to track the asteroid’s movement and further refine its orbit.
Richard Binzel, a professor at MIT, emphasizes that while astronomers are actively tracking the asteroid, they cannot predict with certainty whether it will miss Earth. He likens the uncertainty to a long fettuccine noodle spanning across the moon’s orbit, stating that more data will help pinpoint the asteroid’s position and reduce the impact probability over time.
Source: https://edition.cnn.com/2025/02/19/science/asteroid-2024-yr4-earth-collision-risk/index.html