Asteroid 2024 YR4: Analyzing the Probability of Earth's Close Call

A rapidly gaining notoriety asteroid is said to have a 3% possibility of crashing into Earth come 2032, marking the highest threat level ever recorded, according to both NASA and the European Space Agency (ESA). This colossal rock, falling under the “city killer” classification, has seen its likelihood of impact creeping upward since its discovery last year. Named 2024 YR4, the near-Earth asteroid was originally assigned a 1% chance of collision upon its public disclosure by NASA and the ESA last month. Procedures stipulate that these agencies must inform the public when such probabilities hit the 1% benchmark, an event that remains exceedingly rare.

Currently, NASA’s Jet Propulsion Laboratory projects a 3.1% chance of impact on December 22, 2032, within a short time frame where the asteroid’s trajectory aligns with Earth’s orbit around the sun. Though seemingly high, this equates to 1 in 32 odds. Alternatively, the ESA’s recent assessment estimates the likelihood slightly lower, at 2.8%. These figures have been adjusted upwards compared to last week, when NASA and the ESA concurred on a 2% probability. However, experts suggest this risk could diminish to zero with further analysis, which will be conducted using the James Webb Space Telescope before the asteroid disappears from view in April.

The increased risk is largely tied to an area of “uncertainty” in space, suggesting the asteroid’s path is not definitively known, as stated by Richard Moissl, head of the ESA’s Planetary Defence Office. “We calculate the Earth’s size—positioned inside this uncertain region—against the total possibly reachable area of the asteroid at that critical moment,” Moissl explained to CBS News last week, illustrating how collision probabilities are established. Since additional data have further defined this vague area, with Earth occupying a larger portion of it, probabilities have risen even though no real changes have occurred, Moissl noted. He assured that given a 3% collision possibility also means there’s a 97% chance of a miss, it’s likely 2024 YR4 will not threaten our planet.

As more precise data is gathered, the uncertainty zone is expected to shrink, reducing Earth’s presence within it. Eventually, experts foresee the odds falling below 1% well before April, when the asteroid eludes ground visibility due to its orbit’s distance. Following this, 2024 YR4 won’t be visible again for another four years. Should it make a “close flyby” of Earth, probabilities might see a modest increase, but Moissl assures this does not warrant alarm, although global space agencies regard the slight risk with caution. This asteroid, measuring between 40 to 90 meters, might pose the capability to obliterate a mid-sized city if its size approaches the higher end of estimations, threatening some of the world’s most populated urban centers.