The likelihood of asteroid 2024 YR4 colliding with Earth has experienced notable fluctuations recently, prompting scientists to closely monitor its trajectory. Initial observations from a NASA-funded telescope in Rio Hurtado, Chile, detected the asteroid at the end of 2024, revealing a more than 1% chance of impact in December 2032. However, as astronomers gathered more data, these probabilities shifted dramatically.
On Tuesday, experts reported that the chances of 2024 YR4 colliding with Earth had risen to approximately 3%. This was a surprising increase for an asteroid measuring between 130 to 300 feet in width. Yet, by the following day, the impact probability had decreased to 1.5%. "The impact probability remains small, so people should not really be too concerned about that," reassured Davide Farnocchia, a navigation engineer at NASA’s Jet Propulsion Laboratory.
Such rapid changes in impact probability are not uncommon in asteroid tracking. Scientists initially estimate a collision risk based on limited data, but as more observations are made, they can refine their predictions. The current trajectory range for 2024 YR4 still overlaps with Earth, which explains the increased likelihood of impact at this stage. However, as more data is collected, this range may narrow, potentially eliminating the risk of collision altogether.
The asteroid’s trajectory is currently moving almost directly away from Earth, and astronomers have until early April to monitor its path before it becomes too faint to track. If 2024 YR4 were to collide with Earth, the potential impact zone would be along a “risk corridor” that stretches across the eastern Pacific Ocean, northern South America, the Atlantic Ocean, the Arabian Sea, and parts of South Asia.
Historically, the asteroid 99942 Apophis serves as a reminder of how quickly assessments can change. First identified in 2004, Apophis was once deemed a significant threat to Earth, with early assessments suggesting a possible impact in 2029. However, subsequent observations have since ruled out that risk.
Currently, 2024 YR4 is classified as a Torino Scale 3 object, a designation that indicates a greater than 1% chance of impact, which is relatively rare for asteroids of this size. Even if the asteroid were to strike Earth, it is likely to disintegrate in the atmosphere, resulting in a much smaller meteorite upon landing.
As scientists continue to monitor 2024 YR4, they remain vigilant, updating the public on any changes in its trajectory and impact probability through NASA’s Sentry webpage. The dynamic nature of asteroid tracking underscores the importance of ongoing observation and analysis in understanding these celestial bodies and their potential risks to our planet.