While the asteroid Apophis has been in the news over the past few years about a possible (but unlikely) impact in 2029, a newly discovered asteroid has gotten the attention of astronomers.
What will you be doing on December 22, 2032? Hopefully, just going about your day—but you might want to look up. That night, asteroid 2024 YR4 is expected to pass very close to Earth.
At least, that’s the most likely outcome. However, NASA’s Center for Near Earth Object Studies (CNEOS), which tracks potentially hazardous asteroids, currently (as of February 7) gives 2024 YR4 a 2.4% chance of impact. That’s about 1 in 42 odds—meaning in 41 of those scenarios, it misses.
How Do Scientists Predict an Asteroid’s Path?
Astronomers use telescopes to capture images of the night sky over time, identifying moving objects like asteroids. By tracking these movements, they calculate the asteroid’s orbit and predict its future positions. However, initial observations can be limited, leading to uncertainties. As more data is collected, predictions become more accurate, often reducing the perceived risk of impact.
How Big of a Threat Is It?
One major unknown is the asteroid’s size, which could range from 130 to 330 feet across. This matters because the larger an asteroid, the more energy it releases on impact. For example:
A 130-foot asteroid could explode in the atmosphere, creating a blast wave strong enough to damage buildings over a wide area.
A 330-foot asteroid would be catastrophic if it hit a populated area, potentially leveling a city.
Astronomers are currently using telescopes to refine these estimates. They hope that by April 2025, they’ll have a clearer picture of 2024 YR4’s true size and trajectory. If history is any guide, the odds of impact will likely drop to near zero as more precise data comes in.
What If the Risk Stays Above 1%?
If further observations don’t rule out an impact, international planetary defense teams will have to seriously consider action. For the first time, official protocols for dealing with an asteroid threat could be activated. Some potential responses include:
- Kinetic Impact (DART-Style Deflection)
NASA’s DART mission successfully altered an asteroid’s path in 2022 by slamming a spacecraft into it. A similar mission could be launched to nudge 2024 YR4 off course—but planning such a mission would need to start soon. - Nuclear Deflection
A nuclear explosion near (not on) the asteroid could push it off-course. While never tested in space, simulations suggest a megaton-class nuclear device could break up or redirect an asteroid of this size. However, launching nuclear weapons into space is a politically sensitive and high-risk strategy. - Evacuation & Impact Mitigation
If deflection efforts fail, the only option would be to evacuate the impact zone. However, the exact impact location won’t be known until much closer to 2032. Current models suggest a risk corridor stretching across India, Africa, the Atlantic Ocean, and South America.
What’s Next?
Right now, the most likely scenario is that 2024 YR4 will safely miss Earth. More telescopic observations in the coming months should refine its trajectory and bring impact odds down to zero.
However, planetary defense agencies aren’t taking any chances. In February 2025, the United Nations’ planetary defense committee (SMPAG) will meet to discuss 2024 YR4 and potential response strategies.
For now, there’s no need to panic. A 1 in 42 chance of impact means a 41 in 42 chance of a miss. Scientists are watching—and if action is needed, they’ll be ready.
produced with information from Supercluster and SNEOS.
