Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: WEDNESDAY, May 17, 1995 TAG: 9505170030
SECTION: EXTRA PAGE: 1 EDITION: METRO
SOURCE: GREG EDWARDS STAFF WRITER
DATELINE: GREEN BANK, W.VA. LENGTH: Long
- Genesis 11:6
In a lush Pocahontas County valley, where the surrounding Allegheny mountains hold everything in a protective embrace, scientists are building a modern-day Tower of Babel.
But with a technological twist.
In the biblical tale, the people of Shinar tried to build a tower to heaven; but God stopped their work by stripping away their ability to speak the same language.
At Green Bank, astronomers are building a mammoth tower from which to gaze into the heavens, too; but its purpose is to capture a garble of radio signals emitted by the stars and use it to better understand the universe.
Where the builders of the original tower failed, the scientists at the National Radio Astronomy Observatory near this tiny West Virginia village may look one day - at least figuratively - into the face of God.
The tower that's going up at Green Bank will be the largest fully steerable radio telescope in the world when it's finished in late 1996. It will resemble a big satellite television dish, be 164 feet taller than the First Union office tower in Roanoke, and weigh as much as 41 of Norfolk Southern's largest diesel locomotives.
NRAO engineers designed the telescope, which is being built by Comsat RSI of Dulles, Va., a specialist in antenna construction.
Phase one of the work was completed the first week in May when ironworkers from a union local in Roanoke set the two halves of a 200-ton axle in place atop the telescope's 170-foot tall base. The instrument's antenna, as large as two football fields side by side, will rotate up and down on the axle, whose steel bearings are 40 inches in diameter.
The new telescope replaces a smaller 300-foot-diameter antenna that fell from metal fatigue in November 1988. Green Bank's scientists and local residents worried when the 25-year-old dish fell that it wouldn't be replaced, leaving the observatory without a valuable tool and Pocahontas County with fewer jobs.
However, Sen. Robert Byrd, D-W.Va., rushed an emergency appropriations bill through Congress in 1990, coming up with $75 million to rebuild the fallen dish. A groundbreaking was held in May 1991, and the whole first year was spent pouring 5,000 yards of extra-strong concrete for the 16-million-pound antenna's foundation.
When the big dish fell, the United States fell along with it from first to fourth in the world in radio astronomy, said Richard Fleming, the business manager at the observatory.
The first half of the new telescope's 150-foot-long axle was scheduled to be lifted into place on Tuesday, May 2. Numerous dignitaries were expected at the site to watch the landmark event, a film crew from Charleston was there working on a PBS documentary that will be released once the telescope is finished, and Sen. Byrd was waiting for word that the lift had been successfully completed so he could issue a news release.
It rained hard at times the night of May 1 and as dawn broke on May 2 prospects for the lift didn't look good. For Jay Lockman, an astronomer and the science director at Green Bank, who had looked forward to this day, it was a frustrating time.
A native Pennsylvanian, Lockman, 47, first worked with NRAO in Charlottesville as a co-op student from Drexel University. He has been with the agency for 15 years and has been director at Green Bank for the past two.
Lockman had risen early in anticipation that the axle lift would go ahead as scheduled around 7 a.m. A light rain, however, kept coming and going, teasing him and others who were eager to see the axle go up. Clouds were low around the mountaintops but on the plus side, there was virtually no wind.
Finally, at 9:50 a.m. the rain stopped and four ironworkers inside a square metal basket were lifted 16 stories to the top of the telescope's base where they prepared to guide the axle half into place.
One of those in the basket was Chris Rago, a 23-year-old apprentice ironworker from Clifton Forge. It's not often that an ironworker like Rago gets a chance to work on a project with the status of the Green Bank telescope or one that provides such long term work. Rago had already been on the job for 21/2 years, working six 10-hour days a week.
Rago's good friend, Nick Walls of Richmond, was killed in 1993 while working on the telescope. He was in a basket with three other men when it caught on something and dumped him out, Rago said. After that, workers were ordered to hook up their safety lines while in the basket as well as on the structure itself, he said.
On the ground holding one of the ropes attached to the axle to keep it from spinning during the May 2 lift was another apprentice ironworker, Troy Collier, 23, of Bent Mountain. The more experienced ironworkers tell him the telescope is "a one of a kind job," Collier said.
"It's a once in your career opportunity," said Walter Wise, business agent for Ironworkers Local 167, who had driven up from Roanoke to watch the lift. "You only build the world's biggest ever so often."
The lift was mapped out ahead of time and every man in the air carried a portable radio for contact with the ground, Rago said. Things went a little slower than normal because the 101-ton weight of the axle half had to be kept within the spread of the legs of the derrick being used to lift it, he said.
An American flag hung limp on top of the derrick 450 feet above the ground. The $4 million machine is one of only three its size in the world and is capable of lifting a 135-ton weight with its boom extended 250 feet straight out, Andy Perkins, Comsat RSI's program director at Green Bank, explained.
The axle was freed from its mooring on the ground at 10:25 a.m. but didn't reach the top of the structure until after 11 a.m.
"It went smooth as silk," Collier said of the lift. "The company told us it was a job well done." The workers celebrated a little that Tuesday night, Rago said.
A few days after the first lift, the workers put the second half of the axle, weighing 95 tons, on top of the structure and prepared to jack the two sides together where they would be welded to each other.
Everything about the new telescope - not just its axle - is huge. The base sits on 16 wheels that travel on a circular track 210-feet in diameter. They are driven by 16 30-horsepower direct current motors. Each wheel eventually will support one million pounds.
The telescope's steel beams are hollow square tubes rather than the traditional I-shape. The largest weigh 53 tons apiece. All of the beams are being welded together to avoid the fate suffered by the old dish. Its collapse was found to be related to cracks in the metal around bolt holes.
The reflector dish with a diameter of 328-feet will be assembled on the ground and then cut apart and put back together atop the base, Perkins said. Underneath the dish, 22 steel boxes will hold 2 million pounds of concrete and serve as counterweights.
The surface of the dish will consist of 2,204 thin metal panels that are continually adjusted by computer-controlled motors to keep the dish focused. Lasers on the telescope and ground will help keep its aim to within the space of a dime viewed from a mile away.
Despite its size, the antenna has to be constructed to precise tolerances to maintain its usefulness as a scientific instrument. "What we're doing whether we like it or not," said Perkins, "is we're building a watch in West Virginia."
The new telescope will join several others at the Green Bank observatory, including an impressive 140-foot diameter dish that's used to study immensley powerful objects called quasars and other stellar phenomena. The observatory occupies 2,600 acres of former farmland and backs against the Monongahela National Forest..
Associated Universities Inc., a consortium of nine universities including Harvard, Yale, Princeton and the Massachusetts Institute of Technology, operate the observatory under contract with the federal government's National Science Foundation. Two other antenna sites are Tucson, Ariz. and Socorro, N.M. A large array of telescope dishes at Socorro was featured in the opening of the movie "2010." The observatory's headquarters is in Charlottesville.
One hundred six people work at Green Bank, including six staff scientists and 12 engineers. Each year, 19,000 tourists visit the facility for a free guided tour, and numerous workshops are held for scientists from all over the world. The observatory has a yearly operating budget of $4 million, the same as in 1988. The total operating budget for all NARO facilities is $30 million yearly.
The Green Bank observatory lends its telescopes like a library lends books, Lockman explained. Because high costs make it impossible for most astronomers to have their own radio telescopes, the government lets them borrow the Green Bank antennas for free, if their research proposals pass a peer review.
A telescope's antenna captures radio waves from stellar objects and its computers convert the signals into useful information, including color maps. Different objects emit signals at different frequencies. For instance, astronomers would look for pulsars, rapidly rotating stars that emit radio signals at regular intervals, at low frequencies and at clouds of stellar gas at higher frequencies.
One thing that Green Bank has that no other observatory in the world has is a 13,000 square-mile radio quiet zone. A person can punch the "seek" button on his car FM radio in southern Pocahontas County and it will run the dial continually because there are no signals to find.
The observatory employs a technician whose job is to track down sources of radio static in the area, such as leaky microwave ovens, and fix them. The observatory also monitors applications for such things as cellular telephone towers and works to dissuade their placement where they'll interfere with the observatory.
"By in large we've been very successful in getting people to cooperate with us," Lockman said. But the threats are growing because of the profliferation of pagers, cellular phones and broadcast satellites. And a relatively new threat to the observatory is the seat-back telephone on airliners.
Unlike an optical telescope, a radio telescope can operate day and night and it can "see" things that an optical telescope can't. For instance, scientists using radio telescopes have discovered that dark areas between stars are not empty as was once thought.
In fact, one of the uses of the new telescope will be to study molecules in space. Our own Milky Way galaxy is full for the most part of organic molecules or the building blocks of life. "The chemistry of our galaxy is the chemistry on Earth," Lockman said.
Astronomers have discovered such molecules as water, ammonia and both methyl and ethyl alcohol in space, Lockman said. They've also found formic acid, the chemical that gives the sting to nettles.
Other possible uses for the new antenna will include the precision timing of pulsars to test Einstein's Theory of Relativity, a mapping of the distribution of matter in the universe, and a search for black holes.
The telescope will be able to see a lot more of the sky than the dish that fell, Lockman said. It will be able to operate at frequencies 10 times higher than those of the old telescope and to look right into the center of the Milky Way, something the old antenna couldn't do.
How the telescope will be used will be limited only to the imagination of the astronomers who use it, he said.
Memo: ***CORRECTION***