Astronomers Raise Odds of Asteroid Impact in 2032 to 2.3 Percent—Here’s Why You Shouldn’t Panic

Last week, NASA reported that a newly identified asteroid has a more than 1 percent chance of striking Earth in December 2032, per a statement released by the agency. Now, astronomers have bumped up that number, putting the space rock’s odds of colliding with our planet at 2.3 percent. While the identification has triggered international planetary defense measures, experts say that further observations of the asteroid might drop the impact probability down to zero.

“Most likely this one will pass by harmlessly,” Colin Snodgrass, an astronomer at the University of Edinburgh in Scotland, told the Guardian’s Ian Sample last week. “It just deserves a little more attention with telescopes until we can confirm that. The longer we follow its orbit, the more accurate our future predictions of its trajectory become.”

The NASA-funded Asteroid Terrestrial-impact Last Alert System (ATLAS) station in Chile first reported the asteroid, called 2024 YR4, on December 27, 2024. Within a few days it had risen to the top of NASA’s Sentry risk table and the European Space Agency’s near-Earth object Risk List. In subsequent updates, experts revised its chance of impact to 1-in-63, then 1-in-53, then the current 1-in-43 prediction. That still means, however, that the rock has a 97.7 percent chance of zooming by without causing any damage.

This steady crawl upward is not a reason to panic, experts say. Any prediction of an asteroid’s trajectory at this stage will include uncertainty. And as astronomers gather more data, it will look like the asteroid has a higher chance of hitting Earth—but in all probability, they’ll eventually get enough information to say for sure that it won’t. “This uncertainty is going to be reducing, the impact probability is going to be increasing, until the moment when the Earth falls out of that uncertainty region,” Juan Cano of the European Space Agency tells New Scientist’s Alex Wilkins.

Should you be worried about 2024 YR4? Short answer = no. But I do advise you wear your seat belt when driving! More in this article by The Planetary Society (@exploreplanets). https://t.co/hCUAMFmH2k

— Dr Heidi B. Hammel (@hbhammel) January 30, 2025

Asteroid 2024 YR4 is estimated to have a diameter of around 130 to 300 feet, which is not remotely large enough to be civilization-ending, like the space rock that nearly wiped out the dinosaurs. It’s more comparable to the 1908 Tunguska impactor, which flattened an 830-square-mile area of forest in Siberia. An asteroid of this size still has the potential to destroy a major city or cause a massive tsunami, but in the unlikely case of a predicted collision, authorities would have time to plan necessary evacuations.

However, scientists infer the size of asteroids from the amount of light they reflect, which also depends on their composition. That means astronomers have some inherent uncertainty in their measurement of this asteroid’s diameter.

“If the asteroid has a darker surface, that number is too small; if it has a more reflective surface, that number is too high,” David Rankin, an engineer at the Catalina Sky Survey, told Space.com’s Robert Lea last week. Scientists will be able to more accurately study all aspects of the asteroid, and thus refine their predictions, during its next flyby in 2028.

“The first step in the planetary defense response is to trigger further observations,” Snodgrass explained to the Guardian. “If these observations don’t rule out an impact, the next steps will be more detailed characterization measurements using telescopes and discussion of what space agencies could do in terms of more detailed reconnaissance and eventually mitigation missions. This asteroid is of the scale that a mission like DART could be effective, if required, so we have the technology, and it has been tested.”

NASA’s Double Asteroid Redirection Test, or DART, successfully changed the course of an asteroid by slamming a spacecraft into it in 2022, demonstrating the methodology’s potential to redirect future Earth-threatening objects.

“The international systems we’re putting in place to find, track and characterize—and, if it comes to it, mitigate the impacts of—hazardous asteroids and comets are working as intended,” Andy Rivkin, an astronomer and planetary defense researcher at the Johns Hopkins Applied Physics Laboratory, told the New York Times’ Robin George Andrews last week.

Asteroid 2024 YR4 is currently ranked at level three on NASA’s Torino Impact Hazard Scale, meaning it merits attention by astronomers. The highest ranking an asteroid has ever reached on the scale is four, briefly achieved by asteroid Apophis in 2004 before further observations downgraded it back to zero. It seems likely that this will also happen with asteroid 2024 YR4.

“We expect the impact probability to go to zero rather than 100 percent,” Rivkin said to the New York Times. “But it may take a few years before we get the data to show that.”

Margherita Bassi | READ MORE

Margherita Bassi is a freelance journalist and trilingual storyteller. Her work has appeared in publications including BBC Travel, Discover magazine, Live Science, Atlas Obscura and Hidden Compass.