Gill - If the name "2007TK238" rings no bells, that would not be surprising.

What is surprising, however, is that it was students here at Northfield Mount Hermon School, not some established astronomer, who discovered an asteroid subsequently identified with that number-filled name.

A trio of students in S. Hughes Pack's astronomy class, and Pack himself, got official credit for discovering a group of asteroids while working with the Center for Astrophysics in Cambridge. They used images fed to their computers from a 32-inch telescope in Illinois.

The class pored over the images, primarily to give position reports on asteroids that were already discovered, thereby enabling the center to keep tabs on where the potentially lethal bodies were traveling, and if they were a threat to Earth.

But the students, Wida Li from China, Josh R. Throckmorton from Bedford, and Chelsea A. Bunker of South Deerfield, came up with some blurry, small objects that weren't on anybody's list, and determined they were previously unknown asteroids, which are rocks left over from the creation of the solar system. Their finding was investigated and confirmed by the center.

"Being able to step into the shoes of a professional astronomer, and actually contribute to the world of science, is one of the coolest things I have ever done," said Throckmorton.

And fortunately, the asteroids the students discovered are not headed this way.

"We don't want to be the ones to find the asteroid that hits Earth," Pack said.

Pack, in his classes, tries to impress upon the students the enormity of the consequences should a large asteroid hit Earth, citing it was an event that already happened, wiping out whole species of life. He shows them Hollywood's "Armageddon," in which Bruce Willis leads an expedition of miners to land on an oncoming asteroid to successfully blow it up, a film full of scientific absurdities but which gets the attention of students, he said.

There is little that could actually be done to deter an asteroid, and only with knowing its exact course could an impact area be evacuated, he said, to try to save some lives.

For Pack, as the teacher, the process is the thing.

"These are high school students doing real science. It is not easy and it is mundane - that's what real science is," he said.

Despite the tedium of the asteroid location and positioning work, the students found it thrilling.

"It was really fun, actually," said Bunker.

"It's good to know we are making a contribution while not even into college yet," Throckmorton said.