n a mountaintop in southeastern Arizona
a consortium of American, German, and Italian research institutions is assembling the most powerful telescope in the world.

Two 27.5-foot-wide mirrors of an optical shape and quality once unimaginable are being polished; they will be mounted in a radical new binocular configuration that will allow astronomers to combine and compare their signals. The telescope will see fainter and finer than any ever built. Within the first ten years of the next century it should provide our first real chance of resolving individual planets in orbit around distant stars.

Just down the road from this Large Binocular Telescope (LBT) is a much more modest effort: a 72-inch telescope in operation since 1995. It has served as the testbed for many of the advanced features of its larger cousin, including an f/1 spin-cast mirror (the first ever installed in a large telescope) supported and cooled by temperature-regulated hydraulic fluid and made moveable by computer-controlled direct-drive altazimuth tracking. Responsibility for its design, development, and operation has been shared by engineers at the University of Arizona and Jesuits at the Vatican Observatory.

Using and maintaining an advanced telescope with a number of new and unique features is the challenge that falls squarely on the shoulders of Vatican Observatory Jesuits Fr. Richard Boyle, telescope scientist, and Fr. Chris Corbally, vice director of the Vatican Observatory Research Group at the University of Arizona.

"The day-to-day experience at the VATT (Vatican Advanced Technology Telescope) is one of ladders and slides," Corbally admits, "but that's true of any new telescope." A new computer chip spews out data faster than an aging workstation can receive and process it. New computer software for the altazimuth mount unaccountably and annoyingly "forgets" the location of the telescope while tracking an object across the sky. The hydraulic bearings that are supposed to allow the telescope to move without vibration are subject to unpredictable binding. No sooner is one glitch resolved than another makes itself known. Most engineers allow themselves five years to shake out all the bugs in a new telescope; in this regard, VATT is right on schedule.

Fr. George Coyne, SJ, director of the Vatican Observatory on Mount Graham, is also adjunct professor of astronomy at the University of Arizona.

Yet, one by one, the problems do get solved, and in the past year VATT observers have discovered evidence of possible Massive Compact Halo Objects around the galaxy M-31, a key to understanding the "missing mass" problem in cosmology. Another team has begun a spectrophotometric survey of stars both in our galaxy and in galaxy M-51 that may help us decode the order in which different parts of the galaxy were formed. Another group at the VATT recorded a rare eclipse of Saturn's moons, refining their orbits in a way that may give clues to the internal structure of Saturn itself. Meanwhile, every technical problem solved helps teach engineers about what to look for (and look out for) when the LBT,VATT's larger cousin, is built.

The challenges are not only technical. The observatory is nestled in a mountaintop forest, an island ecosystem surrounded by the southern Arizona desert. This results in some of the clearest, steadiest viewing in the continental United States. But protecting this ecosystem has involved years of careful planning and delicate negotiations with dozens of interest groups. The surrounding forest was left untouched right to the edge of the telescope building itself; as a result, the telescope was in extreme danger when forest fires swept the mountainside during the summer of 1996.

But more than just a mountain's environment is at stake. By studying the universe with the best available tools, Vatican Observatory Jesuits are creating a deeper awareness of our place in the universe. And the interplay of scientific knowledge with religious faith provides a spur and a challenge to both. With that in mind, Vatican astronomer Fr. Bill Stoeger, SJ, and observatory director Fr. George Coyne, SJ, have been involved in sponsoring a series of conferences with the Center for Theology and the Natural Sciences at the University of California at Berkeley on science, philosophy, and theology with the theme "Divine Action in a Scientific Perspective."

Astronomical research has its practical benefits. Distant quasars are nature's high-energy physics laboratories; their behavior can suggest new avenues for laboratory research here on Earth. The behaviors of stars and planets are ideal illustrations of principles of chemistry and physics for undergraduates. And someday we may rely on VATT data to choose which near-Earth asteroid has the best mix of resources for commercial exploitation.

But mostly, throughout history, humanity has studied the stars for the sheer love of their beauty. Today this human need is most easily fulfilled on mountaintops with high-tech instruments. And that means that eager students from less-developed lands are at a distinct disadvantage. Twelve years ago, Vatican astronomer Fr. Martin McCarthy, SJ, proposed a solution to this inequity: a series of intensive four-week summer courses focused on some aspect of astrophysics for students from around the world beginning postdoctoral astronomy studies. These courses, supported by the Vatican, are held at the observatory's headquarters in Castel Gandolfo, Italy. Of the 150 or so students who have passed through these biennial summer schools since 1986, more than 85 percent are still active in astronomy. Many are now professors in countries such as Nigeria and Sri Lanka, where they can transmit this knowledge of the universe to their own people and thus, in Coyne's words, "contribute to the rich cultural heritage of their developing countries."

Besides helping out individual students and fostering the intellectual growth of their home countries, this influx of young and eager scholars has paid dividends for the Jesuits in return. Collaborations begun at these schools can endure for years. For example, Leonardo Vanzi, a graduate of the 1993 school, is now a post-doctoral fellow in Italy preparing an advanced infrared array detector for us on both the VATT and the LBT. His classmate, José Funes, is now a young Jesuit priest who will be joining the observatory staff when he completes his degree.

But even more, the enthusiasm of students gives life to difficult and at times tedious research. "The friendships generated at our schools," notes Coyne, "are one of the results I most cherish. These enduring relationships, both personal and professional, cross over all political, cultural, and religious boundaries."

The tools of astronomy, the VATT and its attendant computers, make up the heart of the Jesuits' work at the Vatican Observatory. But it is the people they touch who make up its soul. When united with a love of creation and a tradition of scientific research, telescopes like the VATT become the world's gateway to the stars.

Favored Status

Who gets to use the Vatican Advanced Technology Telescope? The University of Arizona and the Vatican Observatory share telescope time between them in proportion to the amount each contributes to its construction and maintenance. Some three-quarters of the telescope's cost has been borne by the nonprofit Vatican Observatory Foundation, itself funded by private donors.

This gives the Jesuit astronomers the luxury of being able to schedule large amounts of observing time for long-term projects such as the spectral mapping and classification of stars in our galaxy. That would be impossible to accomplish at publicly funded national observatories such as Kitt Peak, where observers are often lucky to get only five nights a year.

In addition to their own work, however, the Vatican Observatory team has a dream of funding postdoctoral fellowships for young observers from Third World countries. As the funding becomes available, it is hoped that one or two young scientists every year would be supported to observe with the kind of telescope and instrumentation not available to them in most parts of the world. Candidates would include, but not be limited to, graduates of the observatory's summer schools.

Br. Guy Consolmagno, SJ, an astronomer at the Vatican Observatory in Tucson, has a PhD in planetary sciences from the University of Arizona. He taught at Harvard and the University of Nairobi before entering the Society of Jesus in 1989.