If it moves, chances are it's an asteroid. If it doesn't move, it's probably a star. Another Gettysburg physics major, junior Alaine Duffy from Washington Crossing, Pa., took two astronomy classes with Marschall at Gettysburg. When she told him how interested she was in the subject he told her about the small group of students who observe asteroids. Lynch and Duffy said the hours they spend in Gettysburg College's observatory vary from week to week and depend on if the sky is clear and how much work they have for other classes.
Observers use star maps included in the software to identify three or four reference stars.
Snyder's software can then calculate the latitude and longitude of the asteroids by using the reference stars. Before computers, you had to do all the calculations by hand. Astronomers believe there are about 100,000 asteroids in space. About nine years ago, only 10,000 known asteroids had been identified, but now there are 50,000 known asteroids, he said. So discovering one that is not known is quite common, he added.