From Gettysburg Magazine...

and from the Hanover Evening Sun:

"Keeping eyes on the skies:
Gettysburg College astronomy students find new asteroid"
by Suzanne Miller, Evening Sun Reporter

They discovered an asteroid.

During their spring break in March, Larry Marschall, a physics professor at Gettysburg College, and three students went to Flagstaff, Ariz., to use telescopes at the National Undergraduate Research Observatory.  On the first try, they discovered an unidentified asteroid - an irregular chunk of rock.

"We used lucky numbers we got off a fortune cookie at dinner," said Julia Lynch, a sophomore physics major from Buckhannon, W.Va.

To discover new asteroids, members of a Gettysburg College's Asteroid Patrol type in numbers as coordinates in a computer program which then points the telescope to that area in the sky.

After that, a digital camera takes a picture of what the telescope is viewing.  About 15 to 20 minutes later, they take another picture of the same area in the sky.

"In order to take a picture, all we do is this," Marschall said as he clicked the mouse.  "It takes a half minute to get a picture."

They then use the computer to align the pictures on top of one another and start "blinking."  This command flips the pictures back and forth on the screen about every second.

The asteroid observers then look for any spots on the screen that move from one picture to the next.  If it moves, chances are it's an asteroid.  If it doesn't move, it's probably a star.

Astronomy has always interested Lynch and when the opportunity came up to participate in Gettysburg's Asteroid Patrol, "it was almost irresistible,' she said.

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.

The computer program they use was developed by Glenn Snyder, a research associate and computer program [for CLEA] at Gettysburg College.

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.

"Amateurs use software like this all the time," Snyder said. "Before computers, you had to do all the calculations by hand."

Observers also had to manually take pictures and develop the film before you could compare different photographs to one another," Snyder said.

"It is easier to do observations now because of technology and digital imaging," Marschall said.

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.

Although Marschall can act nonchalant about the two asteroids he and Gettysburg students have discovered, Lynch and Duffy think discovering the asteroids is the best part of the program.

After the Asteroid Patrol discovers an asteroid, they must observe it for a few nights, Marschall said.  They then send their results to the Minor Planet Center at Harvard University in Cambridge, Mass. and the center will publish them, he said.

The Minor Planet Center also publishes a list of asteroids that need more observations on a web site on the Internet.  The Asteroid Patrol uses Gettysburg College's observatory  to track the already known asteroids.

In Arizona, the patrol uses stronger telescopes and has less "light pollution" which enables them to make discoveries as well as chart the orbits of known asteroids which are too faint to be seen in Gettysburg.

Marschall, Lynch and Duffy will return to Arizona during their fall break, beginning their trip friday, October 8 and returning Tuesday, October 12.

Lynch and Duffy said when their friends hear they discover and observe asteroids, they always ask "are they going to hit Earth?"

While today many people hear asteroids and think of movies like "Deep Impact" and "Armageddon," Marschall said an asteroid impact that would destroy the world only happens about once every 100 million years.

And, with Gettysburg College's Asteroid Patrol, the Hanover-Adams area will now now about it before the rest of the world."