Asteroid 2024 YR4: Impact Probability Fluctuates, Sparks Torino Scale Discussion

An asteroid named 2024 YR4, estimated to be between 130 and 300 feet in diameter, initially showed a slight probability of impacting Earth in 2032. NASA's initial assessment indicated a 3.1% chance of collision, briefly classifying it as a level 3 on the Torino scale, a system designed to communicate the risk of near-Earth objects. This classification marked the highest impact probability and longest duration above a 1% threshold for any asteroid to date. Improved observations from ground-based telescopes allowed astronomers to refine the asteroid's orbital models, leading to a revised impact probability of 0.28%. Richard Binzel, the astronomer who proposed the Torino scale, noted that such fluctuations are normal as more data becomes available. The Torino scale, adopted by the International Astronomical Union in 1999, aims to provide transparency about potential impact risks, similar to scales used for earthquakes and hurricanes. While the asteroid's threat level has decreased, the event has highlighted the scale's function and the challenges of communicating uncertainty to the public.