When Shoemaker–Levy 9 crossed Jupiter’s Roche limit, its nucleus was torn into 21 fragments—the “string of pearls.” After looping the Sun, those pieces slammed into Jupiter in July 1994 with a force 600× Earth’s entire nuclear arsenal. Events like this remind us how small—and vulnerable—we really are. | The Randall Carlson

In 1994, Comet Shoemaker-Levy 9 collided with Jupiter, becoming the first collision of celestial bodies in our solar system observed by astronomers. The comet, previously split by the giant's gravity, caused the impact of its largest fragment with a power of 6 million megatons in TNT equivalent, exceeding the nuclear potential of the Earth by 750 times. After the collision, dark spots appeared in Jupiter's atmosphere, one of which had a diameter comparable to the Earth. | Jock Williams Meteorolo