Jovian Jolt; September 1993; Scientific American Magazine; by Corey S. Powell; 2 Page(s)

Want to see some fireworks that are literally out of this world? If you are in the neighborhood of Jupiter on the 20th of July next year, keep your eyes open, because nature has scheduled some rather spectacular pyrotechnics. Around that day Comet Shoemaker-Levy 9 will almost certainly crash into Jupiter at a speed of about 60 kilometers a second, annihilating itself as it plows through the thick Jovian atmosphere. The energy unleashed by Shoemaker-Levy's catastrophic demise should approximate that of the devastating asteroid impact on the earth thought to have killed off the dinosaurs. "It's a once-in-a-millennium event," marvels Eugene M. Shoemaker of the U.S. Geological Survey, who discovered the comet this past March 24 with his wife, Carolyn, and veteran comet hunter David H. Levy.

From the start, the three astronomers realized they had bagged no run-of-themill comet when the first photographs showed it to have a bizarre elongated shape. A better image revealed the reason for the comet's odd appearance: it consists not of a single nucleus but of 21 or so bits of frozen gas and dust, stretched out in a line like a string of celestial pearls.