In Arizona: White-Knuckle Astronomy

By Stephen Northup

Marcia Rieke sits on a mound of dirt on a cold mountaintop, nearly two miles up in the clear Arizona sky, watching the sun go down and worrying. A shadow slowly creeps past her, cast by a nearby tan, four-story building that looks like a gigantic bread box. Inside the bread box is the Multiple Mirror Telescope, the world's third most powerful telescope. It looks like no other. There is no glistening dome; it might be a four-story barn. But there are 800 * tons of it, and it turns. The whole structure can pirouette 360 degrees, enormously simplifying the aiming of the instrument. It is probably the world's only building with snowplow blades on its corners to clear a path as it rotates about a circular track. When its doors open, they reveal not a sleek, tubular telescope, but a six-eyed monster, a hexagonal array of half a dozen 72-inch mirrors, the sum of whose images equals the capacity of a single mirror 176 inches across.

None of which bears directly on the reasons why Rieke, a professor of astronomy at the University of Arizona, is worrying. She's been planning for this night for most of a year. Her invitation was an intriguing one: "If you want to see some real white-knuckle astronomy, be out here on the 14th." Astronomy isn't normally considered as nerve-racking a profession as, say, commodities trading or the high wire. This is a mistake. There is great tension, and it comes from scarcity. The mountains around Tucson, the "astronomy capital of the world," may bristle with telescopes, but they are mighty rare in the remainder of the world. There are about 500 American astronomers who publish at least one scholarly paper a year; there are only eight telescopes large enough to see the extremely faint and faraway objects of interest to many of them.

Rieke has driven to the mountaintop with her husband George, also a professor of astronomy at the University of Arizona. The two of them are part of a team that made headlines around the world this winter when it announced the discovery of what appeared to be new galaxies farther out in space and back in time than any other yet seen. Tonight they plan to use the experimental Red Channel Spectrograph, which "sees" deep red light when looking at a galaxy known as M82. Their "eyeball," the spectrograph, is supposed to analyze light that has passed through the telescope, pick out energy in the deep red frequencies coming from the galaxy, and display it on a television screen in symbols that may help the Riekes understand what is going on out there. Deep red light passes through galactic dust more easily than most other colors, and the Riekes are hoping to use the telescope and the spectrograph to penetrate the dust obscuring what they believe is a nursery of new stars. Explains Marcia Rieke: "This galaxy has made a whole lot of new stars, and very recently." Furthermore, she notes, "this guy is in the neighborhood, close by, at 10 million light-years." The edge of the universe is, by some estimates, 15 billion light-years out there, and the M.M.T. can cover four-fifths of the distance.

Before a stargazer can even think about reaching those distances, it is necessary to get to the Arizona mountaintop. That's a tough trip, and one with two parts. First, the observer, who can be astronomer, physicist, mathematician or even chemist, applies well ahead of time to a screening committee of scientists. If the proposal is new, interesting and most likely doable, it is considered. "Most nights are oversubscribed by 50%," says Rieke, "and it can run as high as four times." Then there is a joker in the deck. If you as an applicant are approved and given a night or nights, that is your time. If it rains or clouds over, it is nevertheless still your night, and there are no second chances. You go back to the end of the line. On these mountains Mother Nature bats last.

The second part of the trip to the telescope is equally arduous. Marcia and George and their companion had just spent nearly two bone-shaking hours in a four-wheel-drive carryall with a light-year of mileage on it. The telescope perches on the summit of the mountain on a rocky outcrop that looks as if it were reproduced from a Chinese print. The road would intimidate a mountain goat. Two-thirds of the way up the 18 kidney-crushing miles to the summit we start running into snow on the road, and it is cold.

But then come Marcia's worries, and they are manifold: there are vigorous- looking clouds about, and it is cryptically announced that there are "some problems" with the Red Channel Spectrograph. Marcia has expressed earlier concern about the gadget, "about as big as a small outhouse," which contains a million transistors and costs $200,000.

A word here about the process of astronomy:

-- Rarely, rarely, does anyone actually look with an eye through one of these big telescopes. The "eye" now most probably is a charge-coupled device, the same electronic "film" that makes home video cameras work -- except this electronic film is of extraordinary sensitivity.

-- Nobody wears tidy white laboratory coats. It is bloody freezing cold in the mountains, and the entire crew pads about swathed in layers of wool and copious amounts of down, like multicolored Pillsbury Doughboys.

"Some problems" with the Red Channel Spectrograph has but a single translation: the miserable thing won't work. It was performing perfectly in the Tucson lab, but it is being balky here at the telescope. These edge-of- the-possible electronic devices resemble the little girl with the curl: when they work, they can be wondrous, opening up both vistas and questions; when they quit, they can make you crazy.

Because the Red Channel Spectrograph is ailing and the Riekes are sharing the night with another astronomer, who is going first, there is nothing to do for a while. We drive a couple of hundred yards down to the common room, a comfortable building that houses a kitchen, a pool table, a satellite-dish TV, chairs and couches, and a library. After a quick microwave dinner, the Riekes go back to the M.M.T., where things are still not going well. Glaring at a spectrograph that has smeared a useless mess across the screen, George mutters, "This run is slightly snakebit." "Snakebit?" Marcia asks. "More like cobra-bit." It's now 8:45. Marcia's object, M82, is due to become visible in a little more than four hours, and still the red channel isn't working. Marcia retreats to a corner in one of the labs, produces a hand-held calculator and a big stack of printouts, and proceeds to "crunch numbers." By 9:15 she becomes restless and wanders back downstairs. "I'm gonna see what those guys are doing." The red channel is having all its circuit boards replaced one by one. The changes do no good. Next the cables are switched about, likewise to no avail. 10:02. Marcia: "We're getting to a time where we're going to have to make a brutal decision." 10:12. Marcia: "This ain't a winner. I thought all we had to worry about was the weather." 10:20. Marcia: "We're dead in the water." The Riekes make a decision: they are going to give up their section of the night to the other astronomer, who's not using the red channel of the spectrograph. "This is the first time this has happened to me in a long time," says Marcia. "We'll just apply again." Back to the end of the line. Marcia and George go down to the common room for a little commiseration -- and get it. A small, very late-night toast is offered. Morning arrives, and after too few hours of sleep in the mountaintop's minimotel, the equanimity of the night before has given way to a little ire. "A night like this could be career damaging to a 'post-doc,' " explains George. "They have only two years and, if lucky, ten viewing nights to prove their merit as astronomers."

George and Marcia prepare to head down the mountain and home. The day is clear and still cold. They drive back up to the M.M.T. to gather their equipment. Marcia, her arms full of tapes, papers and a computer, sidles over to the spectrograph, now completely sealed in its hard case, and delivers a small, satisfying kick. Then the Riekes climb into the truck and trundle down the mountain.