City-Killer asteroid 2024 YR4: NASA raises alarm over potential Earth impact

A newly discovered asteroid, 2024 YR4, has caught the attention of astronomers worldwide as NASA confirms its increasing probability of striking Earth. Initially spotted on December 27, 2023, by the El Sauce Observatory in Chile, this space rock now has a 3.1% chance of impact on December 22, 2032—the highest probability ever recorded by modern forecasting systems.

A Potentially Devastating Impact

Measuring between 130 and 300 feet in diameter, 2024 YR4 is roughly the size of the Statue of Liberty. Though not large enough to cause global devastation, scientists warn that an impact could obliterate a city. Traveling at nearly 40,000 miles per hour, the asteroid’s collision could unleash energy equivalent to eight megatons of TNT—500 times more powerful than the Hiroshima bomb.

Where Could It Strike?

NASA has identified several regions in the potential impact corridor, including the eastern Pacific Ocean, northern South America, the Atlantic Ocean, Africa, the Arabian Sea, and South Asia. Populous cities like Mumbai, Kolkata, Dhaka, Bogotá, Abidjan, Lagos, and Khartoum lie within the projected risk zone, putting over 110 million people at potential risk.

Scientists Monitor the Situation Closely

NASA and the European Space Agency (ESA) are continuously tracking 2024 YR4’s trajectory. The ESA currently estimates the impact probability at 2.8%, slightly lower than NASA’s calculations. The International Asteroid Warning Network (IAWN) issued an alert on January 29, when the probability surpassed 1%. Since then, astronomers have been refining their calculations as more data becomes available.

Experts emphasize that the risk could decrease with further observations. "This is not a planetary crisis at this point," said Richard Moissl, head of ESA’s planetary defense office. "It’s not the next dinosaur killer, but it could be devastating for a city."

Learning from the Past: Comparing 2024 YR4 to Apophis

The threat posed by 2024 YR4 has surpassed that of asteroid 99942 Apophis, which once had a 2.7% chance of impacting Earth in 2029 before subsequent observations ruled out the risk. However, astronomers warn that even small objects in space could alter an asteroid’s trajectory, keeping the threat unpredictable.

Unlike Apophis, which is about 1,100 feet wide, 2024 YR4 is much smaller but still dangerous. If it enters Earth’s atmosphere, it could likely explode mid-air, similar to the Tunguska event of 1908 that flattened 800 square miles of Siberian forest.

The Race for More Data and Potential Deflection Plans

Given the uncertainty, NASA is leveraging its most advanced tools for further analysis. The James Webb Space Telescope will observe the asteroid in March 2025, providing a clearer picture of its trajectory. Ground-based telescopes will continue monitoring it until April 2025, after which it will become too faint to track until 2028.

Even in a worst-case scenario, there is still time to act. NASA successfully tested asteroid deflection technology in 2022 with its DART mission, which altered the trajectory of a non-threatening asteroid. If needed, similar strategies could be deployed to divert 2024 YR4 away from Earth.

For now, 2024 YR4 remains the only known asteroid with a more than 1% chance of impact. However, scientists remain optimistic that future observations will rule out the risk. "It’s possible that 2024 YR4 will be removed from NASA’s asteroid risk list, as has happened with many others before," the agency stated in its latest report.

As the world watches and waits, this situation highlights the critical importance of planetary defense initiatives in protecting Earth from potential space threats.