Canadian David Levy has now become perhaps one of the most well-known amateur astronomers of all time. In 1993, Levy, along with Gene and Carolyn Shoemaker, was co-discoverer of a comet that was named Comet Shoemaker-Levy 9 in their honour. This comet became famous in July 1994 when it crashed into the planet Jupiter.

Shoemaker-Levy 9 was not the first comet discovered by David Levy. He discovered his first comet in 1984. Since then, he has discovered 20 more comets, 8 from his own backyard and 13 with Gene and Carolyn Shoemaker at the Mount Palomar Observatory in California.

David Levy was born in Montreal in 1948. Even at a very young age, he was interested in astronomy. At age 5, he remembers asking his brother to show him the Big Dipper constellation. At age 12, he was forced to stay at home with a broken arm, so a cousin gave him a book about the solar system. After reading it, Levy knew that he wanted to become an astronomer or someone who writes books about astronomy. In 1965, when he was a teenager, Levy saw his first comet, Ikeya-Seki. Soon he was searching for other comets with his own telescope in his Montreal backyard. Levy continued to look for comets while he studied English literature first at Acadia University in Wolfville, Nova Scotia, and then at Queen's University in Kingston, Ontario. In 1995, Queen's awarded Levy an honorary doctor of science degree for his comet discoveries.

As an author of 12 astronomy books, David Levy combines his interest in writing and literature with his interest in astronomy. His 1997 book More Things in Heaven and Earth was a compilation of ideas from both astronomers and poets about the night sky. David Levy is also an instructional specialist with the University of Arizona's Project ARTIST, a program designed to bring astronomy into the elementary schools of Arizona.

Shoemaker-Levy 9 was such a significant comet because no one had ever seen a comet crash into a planet before. The comet had actually been ripped into a chain of 21 large pieces when it passed close to Jupiter in 1992. When Levy and the Shoemakers first saw the comet, they thought it looked like a string of pearls. The largest comet fragment was a chunk of ice and rock two to three kilometres in diameter, about the size of one of the Rocky Mountains. When it hit Jupiter, the force of the explosion was hundreds of millions of times the force of an atom bomb. It created a mushroom cloud larger than Asia that rose several thousand kilometres above Jupiter's clouds. After the clouds from the many impacts had spread and cooled, they appeared as vast black patches which were visible for months.

The collisions were observed by many astronomy and space exploration satellites. Voyager 2, Galileo, IUE, Ulysses, and the Hubble Space Telescope were all able to view the impacts. The best view was offered by the Canadian astronomy satellite Hubble Space Telescope. This made the event even more exciting for Canadians. Not only was one of the discoverers of the comet Canadian, but the satellite used to observe its impact was Canadian as well.