The Leonids are coming! The Leonids are coming! NASA and the US Air Force have teamed up with Russian Space Command to prepare for the invasion, astronomers around the world are looking skyward, and people are seeking clear skies in droves for the great Leonid shower.
The Leonid meteor shower is a barrage of shooting stars produced by the trail of a passing comet that appears every year on or about November 17. Leonids are quick, bright meteors that enter the atmosphere at about 158,000 miles per hour, frequently leaving glowing trails for seconds or even minutes after they are vaporized.
So called because they appear to radiate from the constellation Leo, Leonids have been reported as far back as A.D. 902. Chinese astronomers at the time reported that "stars fell like rain" and the Egyptians declared 902 "the year of stars." In 1366, Portuguese observers thought the Leonids heralded the end of the world. In 1625, Korean astronomers reported that "many stars fought and died in the west." Spectators of 1833 Boston reported that "the frequency of meteors were half that of flakes of snow in a snowstorm."
Thirty-three years later, Horace Tuttle and Ernst Tempel independently observed a dim comet, calculated its orbit, and secured a place in the annals of astronomy. Now referred to as comet Tempel-Tuttle, the orbiting body they discovered is the source of the Leonid meteor shower that has fascinated mankind for nearly 1000 years.