In a rare "time-critical" decision, the James Webb Space Telescope will study the true size of the "potentially hazardous" asteroid 2024 YR4 twice over the next few months. The asteroid has a roughly 2.3% chance of impacting Earth in 2032.
An impact from such a rock wouldn’t trigger a mass extinction like the much larger, dino-snuffing Chicxulub impactor did 66 million years ago. But an asteroid that size could wreak regional havoc similar to the Tunguska impactor that flattened some 80 million trees in the Siberian wilderness in 1908