(6/2005) - It is past 10:00 p.m. when physics instructor David E. Holzwarth '78 fishes a key out of his pocket and unlocks the door to the building that has fired his imagination and consumed his thoughts for the past few years. Behind him a handful of students crane their necks to look at the first stars appearing above the horizon of a dark May sky.

At first glance, there's not much to see. Not until they step inside The '38 Observatory, Mercersburg's newest science facility. With the press of a button, the hipped roof, looking like the top of a covered bridge, rolls slowly off the building onto an adjacent frame supported by wooden piers, leaving the entire celestial sphere for a ceiling. Housed inside are two LX 200 12" Meade reflecting telescopes equipped with multiple lenses. They are joined by an 8" Celestron telescope equipped with a CCD (change-coupled device) camera system to enable students to venture into the exciting world of astrophotography and image processing. On this night in May, however, it's enough to look into the past at stars and moons and nebula thousands of light years away, and to contemplate a universe that, for all man's scrutiny, remains a mystery.

"Let's look at Jupiter," say Holzwarth. He picks up a paddle, a numerical keypad resembling an oversized calculator, presses "G" for "star" followed by "905" for Jupiter. For a moment the only sound in the observatory is the whir of a motor located in the mount as it rotates the telescope to fixate on its target. Tonight, three of Jupiter's 61 moons are visible, along with two rings whose dark bands encircle the planet in perfect symmetry. Time evaporates as people take turns at the two telescopes, alternately seeing not only Jupiter, but also the rings of Saturn, not to mention a satellite that happens to fly by.

"Most of our students have grown up in a city or town where the night sky is not that brilliant. Here, in our rural setting, we have the unique advantage of a minimum of reflected ground light. So, we have wonderful skies out here," says Holzwarth.

"When The '38 Observatory was being planned, we felt and still feel that the study of astronomy is something that should be integrated into what we already do and what we do well rather than make it a stand-alone course, at least in the beginning," says Holzwarth. He saw the facility as a vehicle to enhance a conceptual physics course that addresses such principles as gravitation, electricity and magnetism, waves, optics, and relativity.

Holzwarth prepared the formal proposal for the facility once the funds became available. Included in the proposal was the recommendation that the facility housing the telescope depart from the traditional dome structure and consist instead of a building with a roll-off roof. "This was not an easy call," says Holzwarth. "Domes lend themselves to better climate controls and more powerful instrumentation, but only one student can make an observation at a time. We sought a teaching facility large enough to accommodate an average-sized class of 12 students, using several telescopes at the same time."

As Holzwarth pondered what would best fit into his budget, he estimated that the costs for an observatory with a roll-off roof would leave approximately $20,000 for equipment. Initially drawn to a 16" Meade LX 200 telescope priced at $14,000, Holzwarth eventually decided on the next largest model, whose $3,900 price tag would enable the school to purchase two 12" telescopes, an 8” telescope, a CCD camera, a laptop computer, and the lenses, filters, and other peripherals necessary to maximize the learning experience he envisioned.

"The size and quality of a mirror on a telescope relate to its light-gathering capabilities," says Holzwarth. "The larger the mirror, the better one can see a star with low luminosity. As the program grows, a 16" telescope would enhance viewing, but for now, the 12" is fine. It's easy to handle, one that a student can manage." Jeffrey L. Baumgardner '65, senior research associate at the Boston University Center for Space Physics, would concur. "A 12" telescope today with a CCD camera is the equivalent of a 40" telescope 30 years ago because of the increased sensitivity of the detector."

CCD cameras make use of an imaging chip placed on a telescope in lieu of a standard eyepiece. "When looking at an object through an eyepiece, there's not enough light coming into the eye for the brain to perceive what's really there," says Holzwarth. "I might look through an eyepiece and see a little fuzz, but if you expose the image with a CCD you might see a double whirlpool galaxy. The chip is so small and the light it gathers so concentrated, you only need a few seconds of exposure time. What the CCD camera allows you to do is remember more of the light and then transfer the image to a still photograph."

With the attachment of a colored filter wheel, the possibilities are even greater. "You can take multiple pictures using different colored filters and then layer them to create the image," explains Holzwarth. "Students will be able to take these images and make adjustments to them through Photoshop, learned in a course we teach here. It's a way of archiving the learning experience. It's much more personal than looking at those big coffee table books that show, say, images from the Hubble Telescope."

Even without a CCD imaging system, there's plenty to learn. Take star alignment. "A telescope doesn't know where something is until it has a reference. That's why we do star alignment," says Holzwarth, adding that there are quick reference guides indicating which stars can be used for alignment in different months. For most of the year, however, he and his students have used Arcturus, a star in the constellation of the Bear Driver that is 80 times brighter than the sun, although its distance from Earth (37 light years) makes it appear dimmer. Significant in the history of astronomy, Arcturus was one of the first stars for which motion was detected by comparing its position in ancient catalogs with its position more than a thousand years later, thus dispelling the myth that stars are "fixed".

"[The students] are amazed at what they can see up there," says Holzwarth. "I have students who want to camp out in there overnight. These students are very visual, but the images they see on DVD's and computers are all artificial. Here the light they are seeing is unfiltered, unadulterated. When students become aware about distance and the scale of the universe, they are amazed."

Instructor Allison Henle agrees. "I remember when three of my advisees went out to look at sunspots. I don't think I've seen them that worked up in a long time. My hope is that this interest in astronomy will persuade more students to take more science. My ultimate dream would be a succession of three term (10-week) courses – one on solar astonomy in the fall, planetary astronomy in the winter, and the study of stars in the spring.”

Until that happens, there are plenty of opportunities for independent study, such as looking at the luminosity of pulsars or the pitch of Jupiter's moons. Senior Anna J. Petry, who plans on continuing her studies in astronomy when she heads off to college, learned enough about the operation of the telescopes and alignment of stars to serve as a teacher for her peers last spring. "I especially liked observing Jupiter,"  she says. "Every time I looked it was different.”

Senior Robert W. Rice spent the fall learning how to mount and fine tune telescopes, then delved into college textbooks to add to his knowledge of the objects he discovered in the observatory. "My grandmother fueled my interest in astronomy," says Rob. He's already planning a trip with his grandmother to visit major observatories in the west.

Although the astronomy program at Mercersburg is still in its early stages, Holzwarth is satisfied that it is already achieving one of his objectives – awakening the curiosity of his students. "Even students for whom science is a challenge get excited."

As students get more comfortable with the existing equipment, he plans to begin using The Sky, a software program that will enable them to access star charts and data, as well as to control the telescopes by means of computers. With an internet connection, students can have access to the databases that are out there and call up star charts for the time of day and location of where they are. The paddle could be in a virtual mode on the desktop so that instead of the hand control, they could control it through the computer screen. That will also allow them to use the equipment spontaneously without getting bogged down in the many peripherals. The question is, at what point do you stop integrating technology, particularly if things are already working well?

As for the future of the program, the sky's the limit if resources can keep pace with possibilities. For now, however, Holzwarth couldn't be more pleased with how things have turned out. “Every year you ask yourself if you’re growing, if you're doing something that's of use to someone. I was fortunate to take it to this stage, and that feels good. We've got a wonderful facility. As simple as it is, it works well.”