Radio Telescopes: The Future

It was a beautiful sunny day in a Maryland suburb of Washington, DC. I was working on my home computer in preparation for an observing am on the 300-ft diameter radio telescope at Green Bank, West Virginia. The phone rang. It was my wife, calling from the Goddard Space Flight Center where she was working at the time.

'"Have you heard what happened to the 300-ft?" she asked.

Surprised by this unexpected question I tried to imagine what would be the most inappropriate answer and responded, "Has it fallen down?"

"So you have heard."

"It collapsed last night."

'1 don't believe you," 1 exclaimed.

But it was true. During the evening shift the telescope operator housed in the control room beside the telescope heard a very strange, sighing sound, almost ghostlike, and very loud. In a panic he rushed out of the building and headed to the control room of the 140-ft telescope a good half-mile away. After being consoled by the operator 011 duty at the 140-ft, he drove back to the 300-ft and was utterly horrified to see it 110 longer looming above the control room against the dark hillside beyond. Instead, there it lay, a pile of twisted metal where once this giant had stood, gathering faint radio signals from the depths of space.

Months later the likely cause was diagnosed. Metal fatigue, combined with a patchwork of fixes of cracks over a number of years to strengthen the girders holding the telescope together, had caused stresses and strains to be transmitted within the structure to the point where a key element gave way. One thing led to another and the massive structure sagged to the ground with a sign and a groan, frightening the only witness nearly out of his wits.

And thus began a new saga in the history of the National Radio Astronomy Observatory (NRAO) in Green Bank as Senator Robert Byrd, Chair of the US Senate's Appropriations Committee, made it clear that something had to be erected to replace the ruin so as to assure the continued operation of the observatory in what was otherwise a struggling community in West Virginia.

And thus it came to pass that the Robert C. Byrd Green Bank Radio Telescope (the GBT), a 100-m diameter (330 ft) beauty, arose in its place at a cost of some $5 million, a radio telescope now used to probe the distribution of complex molecules between the stars and the ticking of mysterious distant clocks known as pulsars.

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