(CNN) Tiny particles recovered from the summit of a mountain in Antarctica are clues that a meteorite more than 100 yards wide exploded in the sky 430,000 years ago, sending a fireball of vaporized extraterrestrial material to the icy surface, according to new research. Identifying these space rocks, however, is much harder because they leave few traces in the geological record. "Asteroids must be sufficiently massive to make it through the atmosphere and reach the ground with enough speed to form an impact crater. It would have meant lots of them interacting with each other when they were at a very high temperature. This is an artist's rendering of a touchdown impact event over Antarctica.

Source: CNN March 31, 2021 18:00 UTC