Levy, David H. (1948) is an amateur astronomer who helped discover the Shoemaker-Levy 9 comet. A comet is an icy body that normally travels around the sun in a long, oval orbit. Comets are named after their discoverers.
Levy was born in 1948, in Montreal, Canada. As a child, he became enchanted by the night sky, with a special love of comets. He received his B.A. degree from Acadia University, in Wolfville, Nova Scotia, in 1972, and his M.A. degree in English literature from Queen's University at Kingston, Ontario, in 1979.
In 1979, Levy moved to Tucson, Arizona, a center for astronomy because of its clear skies. He discovered his first comet in 1984 from a small observatory he built in his backyard. Levy became one of the world's top comet hunters, eventually finding 21.
In March 1993, Levy and astronomers Eugene Merle Shoemaker and Carolyn Shoemaker discovered a comet near Jupiter. The comet, later named Shoemaker-Levy 9, probably once orbited the sun but had been pulled by Jupiter's gravity into a two-year orbit around the planet. The comet broke into 21 pieces that collided into Jupiter on July 16, 1994.
The impacts caused large explosions that scattered comet debris over large areas. The debris gradually spread into a dark haze of fine material that remained suspended for several months in Jupiter's upper atmosphere. If a similar comet ever collided with Earth, it might produce a similar haze which, if it lasted long enough, could destroy all life.
Levy has received many awards and written many books and magazine articles. Books that Levy has authored or coauthored include Observing Variable Stars: A Guide for the Beginner (1989), The Sky: A User's Guide (1993), The Quest for Comets: An Explosive Trail of Beauty and Danger (1994), Impact Jupiter: The Crash of Comet Shoemaker-Levy 9 (1995), Comets: Creators and Destroyers (1998), and Cosmic Discoveries: The Wonders of Astronomy (2001).