Where earthlings listen to sounds from outer space

In a remote part of West Virginia, scientists monitor the heavens

Short Hop

October 03, 2004|By Jerry V. Haines | Jerry V. Haines,Special to the Sun

Tip No. 1 for a trip to Green Bank, W.Va.: Pack lots of CDs.

If you hit the "scan" button on your car radio, all you will get is an endless display of numbers as the radio searches vainly for a station. There aren't any.

There isn't much else out here in east-central West Virginia, either -- just an occasional farm, a logging truck or, scampering back into the Monongahela National Forest, a deer. The trip here, via routes 55 and 28, winds up into the clouds where snakes of mist curl around the road. When you come down, it's into narrow little plains where you can see patches of sheer rock face on the cliffs above, where the forest seems to have lost its grip and slid screaming to the valley floor.

Then, just past the tiny community of Arbovale, something decidedly extraterrestrial looms above the trees of the Deer Creek Valley. It looks like the biggest darned TV satellite dish you've ever seen.

What are they trying to do, you wonder, watch Martian soccer games? Actually, that's pretty close. They're observing the birth of new stars, the death of old ones and waiting for ET's mom to return his call. And scientists are also listening to signals that left the edge of the universe 14 billion years ago.

This is the National Radio Astronomy Observatory at Green Bank, a facility that for the past 45 years has been studying the heavens. It's 65 miles west of Staunton, Va., and 53 miles south of Elkins, W.Va.

"Observatory" would be an odd name for a place with no telescopes. But there are telescopes here -- they just don't look like it. That big antenna and its seven smaller siblings are just as much telescopes as the Hubble or Mount Wilson scopes. It's just that here they collect radio waves rather than light waves.

That is why there are no radio stations or cellular telephone towers nearby. Just as you wouldn't want stray light beams shining into an optical telescope, a cell phone call, a malfunctioning auto ignition system or a leaky microwave oven can mess up the operation of a radio telescope.

NRAO's Green Bank facility is remarkably open for a place that seems like the stuff of science fiction. You can walk up close to the base of the big dish (the Green Bank Telescope, or GBT, as it is called) and stare up at it all you want. Local residents may walk their dogs, ride their bikes or jog past you as you do.

Although it also has one inactive Navy antenna on the premises, the facility is not run by the Defense Department, the CIA or any agency from the Men in Black movies. It is an educational installation, operated by the National Science Foundation via a consortium of universities.

Tours for public

Consistent with the educational mission of the place, NRAO conducts tours of the grounds and the control rooms, and last year opened the public Science Center, where people of varying levels of technical sophistication can learn how astronomers "see" the universe by listening to it.

A tour begins in the lecture hall, where guides bring out that popular Mr. Science staple, liquid nitrogen. They dip an inflated balloon into a pail of the super-cold stuff, and the molecular action inside diminishes, causing the melon-size balloon to shrink to the size of a lime.

The circuitry in the telescope is similarly cooled; otherwise, it would be overpowered by the noise of copper molecules in its own wiring. It's that sensitive.

(Then the guides delight the crowd by pouring the leftover nitrogen onto the rug, where it vanishes in a paroxysm of vapor, like the Wicked Witch of the West.)

The telescope is located where it is, the guides explain, because it had to be someplace quiet. Green Bank lies sheltered between two mountain ranges in a sparsely populated area unserved by major highways. That's a good thing, if you're a radio astronomer, because just about everything man does generates electrical noise.

Working with the FCC and other agencies, NRAO established a 13,000 square-mile area extending from Clarksburg, W.Va., in the northwest to south of Charlottesville, Va., in the southeast. In this area, new electronic facilities are authorized sparingly, and only after meeting rigorous interference requirements.

This is the nation's only "radio quiet zone."

(They can't do anything about interference from satellites, though. So you won't need to pack those CDs if you have a Sirius or XM satellite radio.)

The big dish -- so sensitive that it can pick up signals as weak as one billionth of a billionth of a watt -- needs quiet if it is to monitor the explosion of a new supernova 30,000 light years away. While optical telescopes can see stars up to 3 billion light years away, the GBT can hear all the way to the edge of the universe. Scientists can hear remnants of the Big Bang, delayed 14 billion years by its travel and attenuated to a very small hiss.

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