Video shows Arecibo Observatory cables snapping, triggering collapse

ARECIBO, Puerto Rico - Video released by the National Science Foundation (NSF) shows the exact moments the receiver of the radio telescope at the Arecibo Observatory in Puerto Rico collapsed.

Two different angles of the collapse were released and the first shot shows the 900-ton receiver platform hanging when its cables suddenly snap and the receiver falls out of frame. In the second angle, taken by NSF drone, the first cable that snaps triggers subsequent cables to break, and the receiver falls out of frame.

The receiver, which also held the Gregorian dome, fell onto the northern portion of the vast reflector dish more than 400 feet below.

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The NSF had earlier announced that it would close the radio telescope. An auxiliary cable snapped back in August, causing a 100-foot gash on the 1,000-foot-wide dish and damaged the receiver platform that hung above it. Then a main cable broke in early November.

RELATED: Puerto Rico's iconic Arecibo radio telescope to close in blow to science

The collapse stunned many scientists who had relied on what was until recently the largest radio telescope in the world.

“It sounded like a rumble. I knew exactly what it was,” said Jonathan Friedman, who worked for 26 years as a senior research associate at the observatory and still lives near it. “I was screaming. Personally, I was out of control.... I don't have words to express it. It's a very deep, terrible feeling.”

The collapse at 7:56 a.m. on Dec. 1 wasn’t a surprise because many of the wires in the thick cables holding the structure snapped over the weekend, Ángel Vázquez, the telescope’s director of operations, told The Associated Press.

“It was a snowball effect,” he said. “There was no way to stop it.... It was too much for the old girl to take.”

The Associated Press and Storyful contributed to this report.