A newly discovered asteroid has climbed to the top of NASA’s impact risk list after fresh observations doubled its chances of striking Earth in 2032. Recent images captured by the Gemini South Telescope in Chile provide a detailed look at YR4 2024, which measures between 131 and 295 feet wide – roughly the size of a building – large enough to potentially unleash devastating consequences if it were to make contact. With a 1-in-48 collision probability, scientists are closely tracking the space rock, now called “city-killer.”
Though the rising impact risk might seem alarming, scientists explain that it’s a normal part of refining YR4’s orbit. NASA’s Near Earth Objects Studies has been tracking the asteroid closely since its discovery by the NASA-funded ATLAS system on December 27, 2024.
NASA astronomer Bryce Bolin, involved in the photo-op, described the discovery as both a concern and a scientific opportunity. “Only a few asteroids have been studied like this,” he told Space.com. “We took 12 200-second long exposures in the Red band and tracked the motion of the asteroid to obtain these images.”
At the time of the observation, YR4 was about 59 million km from Earth, and the team had to contend with several challenges. The asteroid was so faint that scientists had to use the massive Gemini South telescope in Chile to spot it.
The bright moon, which was 70 per cent illuminated, made it even harder to capture a clear image. Mr Bolin also said that the asteroid was also moving quickly at 0.26 arcseconds per minute, requiring careful tracking to keep it in view.
Experts are also focused on the scientific opportunity that YR4 presents. Mr Bolin said the YR4 was “extremely exciting… for the scientific potential of studying such a small asteroid in high detail.”
NASA’s James Webb Space Telescope is also set to assist with observing YR4, with data collection beginning in early March. Using its advanced infrared instruments, Webb will help astronomers more accurately measure the size of the asteroid and assess the potential impact damage if it were to collide with Earth.
While scientists are still studying the asteroid’s path, a collision could be devastating, releasing energy equal to 8 megatons of TNT – enough to destroy an area the size of Washington, DC.
Asteroid expert David Rankin, who has been tracking YR4, reassured the public that the rising impact odds are expected. He said that the risk will likely decrease once scientists gather more precise data on the asteroid’s orbit.
