In Arizona, there is a pristine peak called Mt. Graham that many astronomers, including some at Harvard, think would make an ideal site for high-powered telescopes.

There is only one hitch--about 132 red squirrels.

Mt. Graham is home to an endangered subspecies of squirrel--Tamiasciurus hudsonicus grahamensis--the Mt. Graham Red Squirrel. Conservationists say construction of the observatory puts the handful of Mt. Graham squirrels, the only ones of their kind on the planet, in danger of extinction.

The six-year battle has split the faculty at the University of Arizona into warring factions, with the astronomers leading the fight for the observatory and the biologists leading the fight against.

One of the telescopes that could eventually occupy Emerald Peak, the top of the 10,720-foot Mt. Graham 75 miles northeast of Tucson, is designed by the Harvard-Smithsonian Center for Astrophysics.

Harvard-Smithsonian's proposed six-telescope array would measure submillimeter wavelengths, light waves shorter than radiowaves and longer than infrared. The Center, a joint venture of the Harvard College Observatory and the Smithsonian Astrophysics Observatory, is deciding whether to place its telescopes at Mt. Graham or at the 13,000-foot Mauna Kea in Hawaii, says Irwin I. Shapiro, director of the Center and Paine professor of practical astronomy.

Shapiro says that the state-of-the-art telescope he envisions has to be up very high to avoid water vapor that can absorb submillimeter waves.

"The ideal place for the submillimeter interferometer [the telescope array] is on a satellite in space, but that is too expensive," says Shapiro.

Shapiro has been in touch with officials at Arizona at least since 1985 about the possibility of housing his telescopes at Mt. Graham.

In February of that year he wrote a memo discussing the Mt. Graham choice and noted that Harvard-Smithsonian could receive some material benefits from opting for the Arizonia site.

He wrote that if the center chooses Mt. Graham to house its telescope, Harvard-Smithsonian Center would use its influence with the U.S. Forest Service to allow development of Emerald Peak. In exchange, Harvard-Smithsonian would receive telescope equipment or viewing time on Arizonia's Max-Planck Radioastronomic Submillimeter.

"We agreed that it made most sense for us to provide this help on a barter basis," states Shapiro in the memo.

Shapiro now says that Mt. Graham was not a controversial topic in 1985 when he wrote the memo. "We did not even know what a red squirrel was," he says.

He says the barter proposal should not be interpreted as meaning Harvard-Smithsonian prefers the Mt. Graham site over the one in Hawaii. "Sometimes it is easy to help your neighbor. If we are involved with a joint project with the University of Arizona, we do things for them, and they can pay us back," he says.

"But that has nothing to do with choosing a site for the submillimeter telescope," he says.