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Arecibo Observatory staff believe one of the remaining suspension cables broke on 1 December, sending the 900-ton instrument platform crashing into the dish.

RICARDO ARDUENGO/AFP via Getty Images

Arecibo telescope collapses, ending 57-year run

The Arecibo Observatory is gone. Its 900-ton instrument platform, suspended above a dish in the karst hills of Puerto Rico, collapsed this morning, at about 8 a.m. local time, says Ramon Lugo, director of the Florida Space Institute at the University of Central Florida, which manages the 57-year-old radio telescope for the National Science Foundation (NSF). On 19 November, NSF decided to decommission the observatory following two cable breaks that put the platform on the brink of collapse. But in the end, it couldn’t survive long enough for a controlled demolition.

“I feel sick in my stomach,” Lugo says, fighting back tears. “Truthfully, it was a lot of hard work by a lot of people trying to restore this facility. It’s disappointing we weren’t successful. It’s really a hard morning.”

Lugo says no one was near the dish when the platform fell. But he did not have all the details on how the structure came down. He believes it was because of a failure of one of the remaining cables connecting the platform to one of three support towers. These cables were carrying extra stress following the two previous failures. And since the Thanksgiving holiday, Lugo says, wires were breaking in these remaining cables at a rate of about one per day. He says he told NSF the structure only had a week or two remaining before it would collapse.

Engineers will inspect the condition of the three support towers today, says Lugo, and see whether they can piece together how it collapsed. He worries about the 130 observatory staff members and their future. “I can’t imagine how they feel,” he says.