80 YEARS LATER, MT. WILSON TELESCOPE IS ON `CUTTING EDGE'.

Byline: David R. Baker Daily News Staff Writer

Filled with the cool, still air of a cathedral and steel-riveted machines of another age, the Hooker Telescope's cavernous dome is a shrine to science's past.

Relics lie scattered in the dim light. Tarnished brass knobs, used decades ago to point the 100-ton telescope, sit next to the gray plastic computer that now does the job. Still standing on a small metal platform is the rickety chair in which astronomer Edwin Hubble reshaped our view of the universe, finding the first evidence that the universe was born in an immense explosion now called the big bang.

But the Hooker Telescope is no dusty antique. A new optical system that takes the shimmer and blur out of starlight has suddenly thrust the Hooker into the forefront of astronomy, with sharper images than any other telescope on Earth.

And as astronomers this weekend celebrate the 80th anniversary of the telescope, once the world's largest, the observatory is humming with activity, staking a new claim to science's future.

``It doesn't just still work - this is the cutting edge,'' said Robert Jastrow, director of the Mount Wilson Institute and a founder of the National Aeronautics and Space Administration.

Some of the world's top astronomers will use the newly rejuvenated telescope, once mothballed for 10 years, to hunt for planets around other stars and examine one of Saturn's moons, looking for the building blocks of life.

Eighty years ago tonight astronomers first peered through the Hooker Telescope and immediately recognized its tremendous power and potential to chart the cosmos.

Astronomy's bright star

Astronomers had already been on the mountaintop for decades. The peak was blessed with clear skies and calm air, with little of the atmospheric turbulence that can scramble telescope images in much the way that heat shimmering above a road will distort distant cars.

As far back as 1888, Harvard University had a research telescope perched on Mount Wilson, 5,700 feet above what was then a much smaller Los Angeles.

Created in 1904, the Mount Wilson Observatory left its mark on science early. In its first five years, founder George Ellery Hale used one of the facility's smaller telescopes to reveal the nature of sunspots, dark patches on the sun that had long mystified astronomers. Hale discovered that the spots are areas of powerful magnetic fields that look dark only because they are cooler and dimmer than the rest of the sun's surface.

Then came Hubble, and a string of discoveries that shattered prior notions about the universe's age and shape. Working with the Hooker Telescope, Hubble proved that the universe was an immense, unbelievably old collection of billions of galaxies like our own, flying away from each other in the void.

But the telescope's early heyday didn't last.

Its majesty surpassed

In 1948, the 200-inch Mount Palomar telescope eclipsed the Hooker as the world's largest. As Los Angeles grew, brightening the night sky, attention turned to more remote observatories.

Finally, the institution that ran Mount Wilson decided to pour its money into new telescopes high in the mountains of South America. In 1985, after years of dwindling prominence, the Hooker was taken out of operation.

The telescope's rebirth came through a new technology, developed by the military, that could remake astronomy.

Called ``adaptive optics,'' the system uses a flexible mirror - making tiny adjustments 300 times each second - to compensate for the atmosphere's distortion of starlight.

``Wherever there's a zig, the mirror puts a zag and straightens out the light beam,'' Jastrow said.

Space-age makeover

Before, images from the Hooker Telescope contained the distortion that plagues all ground-based observatories. Stars would sometimes look like quivering blobs of light, not distinct points.

With adaptive optics, those blobs suddenly sharpened, stilled and hardened.

``The first time I saw it, it was a very spooky feeling,'' said Sallie Baliunas, the institute's deputy director. ``I'd been trained for 20 years to see the image on a screen jumping and jiggling around. The first time I saw the image settle down to a point was eerie.''

The $3 million upgrade was finished in October 1995, and the telescope was reopened to researchers.

Not many get to use it. Unlike most observatories, which give a few nights of telescope time to dozens of astronomers each year, the privately funded Mount Wilson Institute has chosen to pursue a small number of projects, giving selected researchers more time than they could get elsewhere.

Get in line

For those picked, the observatory's conditions are ideal.

Laird Thompson, an astronomy professor at the University of Illinois, spent several nights last week firing a laser 12 miles into the atmosphere above the mountain and using the light beam to calibrate the adaptive optics system. He will spend the rest of the semester at Mount Wilson, a far better place for astronomy than the low-lying, cloud-prone Midwest.

``Everyone in astronomy wants to work at those observatories where the image quality is the best,'' Thompson said. ``This is one of the best in the world.''

Other researchers will focus on the search for other worlds beyond the solar system.

Baliunas is looking for magnetically quiet stars on the theory that planets would be easier to spot there than around active stars. Astronomers also hope to use the Hooker Telescope's clear optics to watch planets forming in disks of dust and gas surrounding young stars.

And still, the observatory's directors are not content. Construction has already begun on a cluster of five small, connected telescopes on the mountaintop. When their images are combined by computer, the $11 million array will have the power to spot a footprint on the moon.

Planet hunting

In spite of the improvements, many astronomers still tend to think of Mount Wilson as a piece of history, said Eric Wilcots, an assistant professor of astronomy at the University of Wisconsin. By focusing on the study of other stars, Mount Wilson has picked a field that draws little interest among many astronomers, who are more interested in studying the formation and nature of the universe.

But astronomers are eager to see how well the adaptive optics system works, Wilcots said. And should Mount Wilson researchers discover a planet, or a planetary system still forming, the observatory will quickly recover some of its past prestige.

Today, those who work on the mountain seem convinced that another major discovery will come through the Hooker Telescope's storied lenses sooner or later. Baliunas said her love for the observatory lies equally in its past and its potential.

``It's partly the history and partly the future - the fact that when I look through it, I think how many other eyes have (looked) through it, and will look through it, and what they might see.''

ASTRONOMY`S BRIGHT STAR

NEW LIFE

``Adaptive optics'' have placed Mount Wilson's 80-year-old Hooker Telescope back on astronomy's cutting edge. The new system uses a flexible mirror - making tiny adjustments 300 times each second - to compensate for the atmosphere's distortion of starlight. The resulting images are sharper than visible light pictures from the Hubble Space Telescope.

MISSION

Unlike other observatories, which give a few days of telescope time to dozens of astronomers each year, Mount Wilson concentrates on just a handful of projects. Right now, the observatory is looking for stars that may have planets around them. Astronomers also hope to use the high-resolution telescope to study planets still forming around other stars.

HOW TO GET THERE:

HOURS: Mount Wilson is open to visitors each weekend from 10 a.m. to 4 p.m. During daylight-savings time, visitors can take free guided tours of the grounds beginning at 1 p.m.

INFORMATION: [phone]

SOURCE: Mount Wilson Institute

CAPTION(S):

3 Photos, Box, Map

PHOTO (1--color) Mount Wilson Observatory's main dome houses the 100-inch Hooker Telescope, which has been peering into space for 80 years.

(2--color) Robert Jastrow, director of the Mount Wilson Institute, stands with the Hooker's original controls.

(3--color) Telescope engineer Joe Russell demonstrates how viewers use an eyepiece for direct viewing through Mount Wilson's 100-inch scope. The gear is part of the clock drive which keeps the 80-year-old telescope centered on its subject.

David Sprague / Daily News

BOX: ASTRONOMY`S BRIGHT STAR (see text)

MAP: (color) HOW TO GET THERE (see text)

Dionisio Munoz / Daily News