It's been several years since the Cornell Astronomy Department lost the National Science Foundation contract to manage the Arecibo radiotelescope observatory facility in Puerto Rico. Just this week the news came that NSF is shutting down the Arecibo radiotelescope due to safety concerns.
NSF says engineers are concerned that the 305-meter telescope structure "is in danger of a catastrophic failure" after two of the cables on a single tower broke several weeks apart. They worry that repair efforts could be unsafe for crews. Instead, they're decommissioning the telescope and planning a controlled demolition before the structure collapses.
We spoke with retired Cornell Astronomy professor Donald Campbell, who was an early researcher at Arecibo after finishing a masters degree in Sydney. He says, "I turned up there in 1965 as a 22-year-old. A year later I went up to Cornell and finished my Ph.D. then came back onto the staff of the observatory for quite a while."
Professor Campbell was the director at Arecibo for several years in the 1980s, and says the radiotelescope's shutdown leaves some Cornell researchers without one of the most sensitive instruments in the field.
"There's been a continued involvement of Cornell faculty, graduate students, and postdocs with Arecibo ever since Cornell left," he says. That includes pulsar work, both to search for new pulsars as well as timing already known pulsars with great precision. As well as looking at Atomic hydrogen to measure the recessional velocity of galaxies by measuring the doppler shift.
The 100-meter Green Bank telescope in West Virginia is still available for measuring pulsar arrival times, but Arecibo is about five times as sensitive.
He says Arecibo had a wire mesh surface when it first opened, limiting its maximum frequency to about 600 megahertz or 57 meters. In the early 1970s the surface was recovered with 38,788 aluminum panels that made its surface much more accurate and allowed it to operate to much higher frequencies, including the 21 centimeter radiation from atomic hydrogen they couldn't observe prior to that improvement.
Cornell researchers are just beginning to consider how losing the Arecibo radiotelescope will affect their work. For now, the NSF still hopes to keep some of the facilities at the complex available.
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