Asteroid Threat Assessment: 3/10 Risk of Impact with Earth in Eight Years

Asteroid Threat Assessment: 3/10 Risk of Impact with Earth in Eight Years

Asteroid 2024 YR4, recently discovered, poses a 1.3% collision risk with Earth on December 22, 2032. Measuring 40 to 90 meters, it has been classified as a hazardous asteroid by the ESA. Its potential impact zone includes parts of the Pacific, South America, and Asia. While current estimates suggest significant local damage, it is unlikely to cause global effects. Tracking efforts are underway, with organizations collaborating to refine its orbital data and assess possible defensive strategies.

The Discovery of Asteroid 2024 YR4

Recently identified, the asteroid 2024 YR4 is already capturing the attention of astronomers and researchers alike. This celestial body, measuring between 40 and 90 meters, has a 1.3 percent chance of colliding with Earth on December 22, 2032. As a result, it has ascended to the top of the European Space Agency’s (ESA) list of hazardous asteroids, prompting a thorough examination.

Potential Impact and its Implications

While the current probability of an impact may be revised as more precise orbital data becomes available, it meets three critical criteria set by the International Asteroid Warning Network (IAWN). These criteria include the likelihood of an impact within the next 50 years, a probability exceeding 1 percent, and a size greater than 50 meters—indicating the potential for significant local damage.

The potential impact zone stretches from the eastern Pacific Ocean, across northern South America, the Atlantic Ocean, Africa, the Arabian Sea, and into South Asia. However, the exact location of a potential strike remains uncertain due to the imprecise nature of its orbit.

At this stage, the anticipated damage from an impact is still being assessed, with estimates suggesting that it could release energy equivalent to 8 megatons of TNT—similar to the explosive power of a hydrogen bomb. Unlike the catastrophic event that led to the extinction of the dinosaurs 66 million years ago, the size of 2024 YR4 is far too small to generate global consequences.

Instead, an impact would likely resemble the Tunguska event of 1908, where an asteroid or comet explosion leveled millions of trees over a vast area in Siberia, creating a significant shockwave. If such an event occurred over a populated area, it could result in extensive damage within a 50-kilometer radius.

The asteroid’s perceived threat is further underscored by its ranking on the Torino Scale, which rates near-Earth objects from 0 (no risk) to 10 (certain collision with global consequences). Currently, 2024 YR4 holds a level 3 rating. Historically, only one asteroid has reached hazard level 4, which was subsequently downgraded shortly after more precise measurements were taken.

As 2024 YR4 continues its elliptical orbit around the sun, completing a rotation every four years, it was first spotted on December 27, 2024, by a telescope in Chile. Notably, it passed Earth at a safe distance of 830,000 kilometers just two days before its discovery, and has been moving away since.

Tracking its orbit has become increasingly challenging. Astronomers have until April to observe the asteroid with powerful telescopes before it fades into the depths of space. Consequently, there is a concerted effort to refine its orbital path.

Organizations dedicated to asteroid tracking are collaborating daily to share crucial information. Additionally, the IAWN has requested observations of 2024 YR4 using space telescopes, with infrared imaging from the James Webb Telescope being of particular interest for accurately determining the asteroid’s size.

Understanding the size of the asteroid is vital for determining necessary defensive measures. Detlef Koschny, head of the Space Mission Planning Advisory Group (SMPAG) for the ESA, emphasizes that if the asteroid’s diameter surpasses 50 meters, consideration of defense strategies will become critical. Given 2024 YR4’s estimated size, it falls into a gray area, prompting the SMPAG to hold off on planning further actions.

Koschny anticipates that more definitive information will be available in the coming months. Simulations suggest that the risk of an impact may be overestimated rather than underestimated. However, the possibility of completely ruling out an impact will likely remain until April. Patience is essential, as it will take until 2028 for the asteroid to approach Earth again for further measurements.