If you’re like most people on Earth, you might want to mark your calendar for December 22, 2032. That’s when asteroid 2024 YR4 has a small chance of colliding with our planet. While the odds remain low—NASA estimates a 2.3% probability of impact—that’s nearly double the 1.2% risk calculated just weeks earlier in January by both NASA and the European Space Agency (ESA). The increase in probability has pushed the asteroid past the 1% threshold, requiring authorities such as the U.S. Office of Science and Technology Policy, the United Nations’ Space Mission Planning Advisory Group, and the U.N.’s Office for Outer Space Affairs to take note.
Before you start panicking, though, it’s important to put things into perspective. This asteroid, measuring between 130 and 300 feet in diameter, is nowhere near the size of the one that wiped out the dinosaurs—estimated to have been six to nine miles wide. However, history has shown that even smaller space rocks can be dangerous. The Chelyabinsk meteor that exploded over Russia in 2013 was only about 65 feet across but still managed to damage 7,200 buildings and injure 1,500 people.
Worry About an Asteroid Hitting Earth?
Scientists assess asteroid threats using the Torino Scale, a hazard index ranging from zero (no risk) to ten (a catastrophic global event). The 2024 YR4 asteroid currently ranks as a three, meaning it has the potential to cause localized destruction but not widespread devastation.
So, should you be worried? Probably not. Unlike some global issues that lack coordination, planetary defense is one area where scientists, policymakers, and international organizations work together effectively. A vast network of space agencies, private observatories, and both Earth- and space-based telescopes constantly track asteroids that might pose even a minimal risk to our planet. Moreover, we now have proof that if a significant threat emerges, we have the technology to alter its course. In 2022, NASA’s DART (Double Asteroid Redirection Test) mission successfully changed the trajectory of an asteroid by crashing a spacecraft into it.
Interestingly, asteroid 2024 YR4 was only discovered recently—on December 27, 2024—by the NASA-funded Asteroid Terrestrial-Impact Last Alert System (ATLAS) telescope in Chile. Its size, speed, and trajectory immediately made it a point of interest. Traveling at about 38,000 mph—more than twice the speed of an Earth-orbiting satellite—it carries significant kinetic energy, making even a smaller asteroid potentially destructive upon impact.
The asteroid falls into the category of a near-Earth object (NEO), a designation for asteroids that come within 1.3 astronomical units of the sun (one astronomical unit is the distance from the sun to Earth—about 93 million miles). Once scientists confirmed its NEO status, ATLAS astronomers quickly alerted key organizations, including NASA’s Jet Propulsion Laboratory, the ESA, and the International Asteroid Warning Network (IAWN), which coordinates tracking efforts among 59 countries and organizations worldwide.
Right now, NASA and other agencies are closely monitoring around 38,000 NEOs, constantly refining their calculations to determine whether any of them pose a changing risk. For now, 2024 YR4 remains visible to telescopes, but by April, it will pass behind the sun and remain out of sight until June 2028. NASA is using this limited window of visibility to gather as much data as possible, including reserving time on the James Webb Space Telescope to study its size, mass, and trajectory in greater detail.
One of the key questions is where, if at all, 2024 YR4 might strike. While Earth is mostly covered in water—meaning there’s only about a 30% chance it would hit a populated area—scientists have outlined a preliminary impact zone stretching from the eastern Pacific Ocean to northern South America, the Atlantic coast of Africa, the Arabian Sea, and South Asia. As the asteroid gets closer, observations will become more precise, allowing for a clearer prediction of any potential impact location.
If calculations confirm a high risk of impact, there are contingency plans in place. With months or even years of advance notice, governments could evacuate high-risk areas. A 2021 U.S. government study on NEO emergency protocols concluded that mitigation measures could include large-scale evacuations and securing critical infrastructure. A 2024 study in Acta Astronautica suggested that, depending on the asteroid’s size, sheltering in place could also be an option. The study compared asteroid impact preparedness to hurricane readiness, recommending reinforced shelters for those near potential impact zones.
Fortunately, humanity is not defenseless against space threats. The success of the DART mission proved that we can alter an asteroid’s path if necessary. In 2022, NASA’s spacecraft deliberately crashed into the small asteroid Dimorphos at 14,000 mph, altering its orbit by 32 minutes—three times more than expected. This landmark test demonstrated that we have the ability to redirect hazardous asteroids given enough time to prepare.
As former NASA Administrator Bill Nelson put it, “This mission shows that NASA is trying to be ready for whatever the universe throws at us. NASA has proven we are serious as a defender of the planet.”
While a fully operational asteroid-defense fleet is still a long-term goal, the current approach—constant monitoring, early warnings, and coordinated global efforts—remains our best line of defense. For now, astronomers will continue scanning the skies, ensuring that if 2024 YR4 or any other space rock ever poses a serious threat, humanity will have the time and means to respond.
