Carolyn & Eugene Shoemaker and David Levy discovered the Shoemaker-Levy 9 comet.
The trio discovered the comet using a rather run-of-the-mill Schmidt telescope while searching the skies for near-earth objects in California. The comet was particularly interesting because it was the first active comet seen orbiting a planet. Even more spectacular was the comet’s collision with Jupiter the following year, as it was the first time in history we could directly observe two objects from the Solar System colliding.