observatories

Visitors Track the Stars at Arizona's Renowned Observatories

Text by TOM DOLLAR

Photographs by EDWARD McCAIN

IN THE REALM of the LONG EYES

TALL MOUNTAINS, OPEN SPACES, clear skies, little air turbulence, mild weather, and the relative absence of "light pollution" from big cities create what astronomers call "good seeing." That's why southern Arizona and astronomy are virtually synonymous.

Several peaks there bristle with telescope installations. There are the University of Arizona's Steward Observatory telescopes on Mount Lemmon and Mount Bigelow; the Smithsonian's Fred Lawrence Whipple Observatory on Mount Hopkins; and the National Optical Astronomy Observatories on Kitt Peak - all within an hour's drive of Tucson. And the Mount Graham Inter-national Observatory sits atop the Pinaleno Mountains near Safford.

But our tour of the telescope sites open to The gateway to Lowell Observatory is the Steele Visitor Center. Tours begin with a lecture and video presentation followed by visits to the Clark Telescope, the rotunda library, the Pluto Walk (a scale model of the solar system), and the Pluto Telescope.

the public started 257 miles north of Tucson in Flagstaff, where the story of astronomy in Arizona originated in 1894 with a man named Percival Lowell. Boston born and bred, Lowell was convinced that "canals" observed on Mars were evidence of intelligent life on that planet. To better study Mars and to substantiate his theory, he established the Lowell Observatory in Flagstaff on what came to be known as Mars Hill.

Lowell was wrong about Mars, but later discoveries by Lowell astronomers earned the observatory a place among the world's best. In the early 1900s, V.M. Slipher, using (PRECEDING PANEL, PAGES 4 AND 5) One of the world's largest telescopes, the National Optical Astronomy Observatory's four-meter Mayall dwarfs the dozen smaller scopes atop 7,000-foot-high Kitt Peak, 40 miles west of Tucson. (LEFT) The observatory Percival Lowell built on Flagstaff's Mars Hill in 1896 houses his original 24-inch Clark Telescope. The 8,000-pound dome rumbles around a circular track on 1954 Ford pickup tires and wheels to align the 30-ton telescope with points in the night sky. (RIGHT) Partially disassembled to show its inner workings, the 24-inch Morgan Mirror Telescope at Lowell provides an opportunity for staff member Jeffery Henrikson to talk to young visitors about how telescopes work.

A spectrographic camera attached to the Clark Telescope, discovered that light sources called spiral nebulae were rapidly receding from our galaxy, the Milky Way. This finding led to the theory of an expanding universe. Later, in 1930, astronomer Clyde Tombaugh discovered Pluto, the ninth planet and the farthest from our sun (see Arizona Highways, May '94).

The gateway to Lowell Observatory is the Steele Visitor Center. Tours begin with a lecture and video presentation followed by visits to the Clark Telescope, the rotunda library, the Pluto Walk (a scale model of thesolar system), and the Pluto Telescope. Before and after the lecture-tour, visitors are free to explore the center's main exhibit, "Tools of the Astronomer."

Although the U.S. Naval Observatory just outside Flagstaff is not open daily for public visitation, group tours of the facility can be arranged. During the Flagstaff Festival of Science, which runs for 10 days each fall, the Naval Observatory offers an open house with public tours on the hour. The Northern Arizona University Observatory also is open for several nights during the festival.

Our next stop is at Kitt Peak, unquestionably the most famous astronomy observatory in Arizona. Located on the Papago Indian Reservation atop the Quinlan Mountains 56 miles southwest of Tucson, the observatory is called "Realm of the Long Eyes" by the Indians.

Because it takes enormous sums of money to build and operate telescopes, consortiums that spread the costs are common in astronomy. Kitt Peak is an example of an astronomy consortium. Two branches of the National Optical Astronomy Observatories — the Kitt Peak National Observatory and the National Solar Observatory - maintain telescopes on Kitt Peak. Other groups have telescopes there as well, including the University of Arizona, Case Western Reserve, the University of Michigan, the National Radio Astronomy Observatory, the Massachusetts Institute of Technology, and Dartmouth College.

One of the best ways to see Kitt Peak is to pick up a tour pamphlet at the visitors center and walk among the installations. It's a good hike, and you can see the peak at your own pace. Docent-led tours also are available.

'Light is time,' astronomers tell us. And the new scope will have more than twice the light-gathering power as the old, enabling it to see faint objects in deep space, farther and farther back in time.

Kitt Peak has scopes to do a large variety of jobs. The four-meter Mayall Telescope, for example, all 375 tons of it, is used to hunt faint distant objects. Looking out on a clear day from the visitors gallery at the Mayall, observers can see more than 100 miles in every direction. The gallery also is an excellent perch for surveying the panorama of Kitt Peak telescopes. At the other end of this veritable astronomy village is the McMath-Pierce Solar Telescope, used exclusively to study our nearest star, the sun. Not all installations here are open to the public, but the ones

IN THE REALM of the LONG EYES

that are represent a sampling of the types of astronomical investigation being done on the mountain. Down the mountain from Kitt Peak, a shaded picnic area offers drinking water, soft-drink machines, cooking grills, and rest rooms. From the picnic area, visitors can see a 25-meter radio telescope, part of the Very Large Baseline Array, one of 10 such installations across the continent. If traveling along skinny mountain roads with steep drop-offs and few guardrails makes your pulse quicken and your palms sweat, you might think twice about visitingthe Smithsonian's Fred Lawrence Whipple Observatory on Mount Hopkins in the Santa Rita Mountains about 50 miles south of Tucson. But you don't have to drive yourself, you can leave that to a tour-bus driver. With a docent aboard, the bus will pick you up at the visitors center at the base of the mountain and haul you 10 miles up the narrow, winding one-lane road to the telescopes at the 8,550-foot summit.

It's worth the trip for at least three reasons: One, the Whipple Observatory's docents are among the best trained in the business, so you'll learn a lot about telescopes to be sure, but also about the flora, fauna, and geology of the region.

Two, up top the views are spectacular. From Mount Hopkins, in clear air, you can see all the major telescope peaks in southern Arizona.

Three, Mount Hopkins is the home of the MMT, the Multiple Mirror Telescope. When it began operating in 1979, the MMT was the world's third-largest telescope, and with six identical telescopes in a single mount, a great innovation in telescope design. In 1979 a telescope mirror larger than five meters in diameter would have been both too heavy and too costly to create. Since then, however, the University of Arizona Mirror Laboratory has refined mirror casting. Now a relatively lightweight mirror up to eight meters across can be cast.

Plans are to replace the six mirrors in the MMT with a single 6.5-meter mirror. Housed in the same building as the original MMT, remodeled for the new mirror, the instrument was scheduled to see "first light" sometime late this year. "Light is time," astronomers tell us. And the new scope will have more than twice the lightgathering power as the old, enabling it to see faint objects in deep space, farther and farther back in time. Travelers can visit the Gov Aker Observatory at Discovery Park in Safford and tour the International Observatory on Mount Graham the site of the two newest telescope installations in southeast Arizona on the same weekend.

Currently under development, Discovery Park will feature exhibits on the cultural and economic history of the area from artifacts of primitive cultures to modern agriculture, mining, and, most recently, astronomy. The Gov Aker Observatory, which is both a museum of astronomy and active observatory, opened in 1995.

The exhibits, many enhanced by interactive computers or videos, feature the origins of the universe; the sounds of space; the history of astronomy; the process of telescope mirror-making; and a flight simulator that takes visitors on a spaceship tour of our solar system. There's also a domed observatory for nighttime star parties. I shared the 20-inch telescope with a den of Cub Scouts from Safford. The high point of our evening's viewing was a closeup of the moon's craters.

The next morning, our van made the long ride up Swift Trail to the Mount Graham International Observatory. The clear autumn day provided grand vistas of the long valleys to the east and west as we ascended several thousand feet and more than 30 miles to the mountaintop. Crimson-leafed bigtooth maples lined the canyon recesses. A few days earlier, a storm had dumped four inches of snow on the mountain, and ragged patches remained on the ground. We toured two of the three telescopes initially approved by Congress: the 10-meter Heinrich Hertz Submillimeter Telescope, a joint project of Germany's Max Planck Institute for Radio Astronomy and the UofA; and the Vatican Observatory's 1.8-meter Lennon Telescope. On a nearby peak, space had been cleared for a proposed Large Binocular Telescope.

The best way I know to rub elbows with working astronomers is to sign up for one of the astronomy camps on Tucson's Mount Lemmon run by Don McCarthy of the Steward Observatory. McCarthy, with the help of UofA astronomy graduate students, offers beginning and advanced camps for adults and teenagers. I joined a group of adult campers at the Steward Observatory's 61-inch telescope atop Mount Bigelow. Most of the campers were dedicated amateur stargazers and comet hunters, many of whom owned small telescopes. For them astronomy camp was a chance to see through a much more powerful optical instrument objects previously observed from their homes. Slightly overcast, it wasn't the greatest night for viewing, but the campers' enthusiasm was undimmed. Few had ever seen a distant star cluster through the eyepiece of a big telescope. The hit of the evening was a glimpse of the planet Saturn, rings and all. One of the unexpected happenings on my grand tour of Arizona's principal telescope sites was an impromptu jig performed by an astronomer inside a major telescope's domed chamber.

IN THE REALM of the LONG EYES

Blaise Danzian was explaining that the CCD (charge coupled device) camera attached to the eyepiece of the 61-inch telescope at Flagstaff's U.S. Naval Observatory works best when cooled by liquid nitrogen to a frigid -200° F. "What happens," said the youthful astronomer, "is that photons, particles of light, are converted by the camera's silicon chip into electrons. The chip holds these electrons in little wells, sort of like these tiles on the floor. But when the CCD is at room temperature, the particles have too much thermal energy, and they do a jittery little dance, so it's hard for us to manipulate them with our electronics." Inspired to demonstrate, Danzian moved his feet together, flexed his arms, and bent his knees slightly. Then he shuffled in place and did a little hop-skip to an adjacent tile. "This energy is what astronomers call noise; it goofs up our measurements. But if we keep the CCD really cold, the electrons inside the chip just sit there, sort of shivering quietly in place." He shivered, looked at his feet, then grinned at me, sheepishly. "I'm Italian," he said, as if to explain. "I guessed," I answered, wondering what Galileo, that other Italian astronomer, would think.

WHEN YOU GO

Arizona's observatories sit on high mountain peaks where temperatures may be 30° F. cooler than lower elevations. Take warm clothing. For information on public programs, tours, and hours, call the observatories. All telephone numbers are in area code 520 unless otherwise indicated. Fred Lawrence Whipple Observatory, Amado; 670-5707. Gov Aker Observatory at Discovery Park, Safford; 428-6260. Kitt Peak National Optical Astronomy Observatories; 318-8200. Lowell Observatory, Flagstaff; 774-2096. Mount Graham International Observatory; 428-2739. Steward Observatory, near Tucson; general information, 621-2288; for information on astronomy camps, 621-4079. U.S. Naval Observatory, outside Flagstaff; 779-5132.