On July 19, 15 years after the Shoemaker-Levy 9 comet slammed into Jupiter, Australian amateur astronomer Anthony Wesley noticed a dark spot near the planet’s south pole that resembled marks he had seen after the 1994 crash. NASA scientists took a closer look and concluded that another comet or asteroid had slammed into Jupiter with the force of 2 billion tons of TNT. The Hubble Space Telescope snapped this photo four days later, showing an enigmatic cloud spread out by Jupiter’s turbulent atmosphere.
