NASA Revises 2032 Impact Risk for ‘City-Killer’ Asteroid in Latest Update

NASA Downgrades Threat of ‘City-Killing’ Asteroid 2024 YR4

NASA has reassured the public that asteroid 2024 YR4, once deemed a potential threat to Earth, now has a mere 1-in-26,000 chance of colliding with our planet in 2032. Updated calculations from NASA’s Sentry system confirm a 99.9961% likelihood the asteroid will safely pass by Earth on December 22, 2032.

From Alarm to Reassurance
Initial observations in December 2024 sparked concern when early projections suggested a non-zero impact risk. By January 2025, the asteroid became the first in years to exceed a 1% chance of hitting Earth. At its peak, the odds briefly rose to 1-in-32 (3.1%), earning it a rare Torino Scale rating of 3—indicating a notable but uncertain threat. However, further tracking shrunk its “uncertainty region,” and NASA has now downgraded it to Torino Level 0, meaning “no hazard.”

Why the Sudden Shift?
Asteroid trajectories are challenging to predict early on due to limited data. As astronomers gather more observations, the margin of error around the asteroid’s path shrinks. Initially, Earth occupied a small fraction of this uncertainty zone, but refined data eventually excluded our planet entirely. “This is the expected outcome,” said Professor Richard Binzel (MIT), creator of the Torino Scale. “Better tracking gives us an ‘all clear.’”

A Close Call for Earth
Classified as a Near-Earth Object (NEO), 2024 YR4 measures 40–90 meters (130–300 ft)—larger than London’s Nelson’s Column. If it had struck, its estimated 8 megaton blast could have mirrored the 1908 Tunguska event, which flattened 830 square miles of Siberian forest. A modern impact on a city could cause millions of casualties.

The Role of Planetary Defense
While deflection missions like NASA’s DART (which successfully altered an asteroid’s orbit in 2022) remain critical, 2024 YR4’s case highlights the importance of early detection. Astronomers stress that frequent asteroid flybys—several yearly—are normal, and improved telescopes will make such alerts more common. However, most pose minimal risk.

Key Facts About 2024 YR4

• Speed: 29,000 mph (46,800 km/h)
• Closest approach: 30 million miles from Earth (current distance)
• Potential impact energy: ~8 megatons of TNT (500x Hiroshima’s atomic bomb)

Looking Ahead
Experts emphasize that increased detection of NEOs reflects advancing technology, not rising danger. “Finding these objects early ensures we’re rarely surprised,” said Binzel. With projects like the Vera C. Rubin Observatory set to scan the skies by 2025, our ability to predict and prepare for threats will only improve.

In the meantime, 2024 YR4’s revised trajectory offers a sigh of relief—and a testament to the evolving science of planetary defense.

(Word count: ~600)