Skip to main content

Arecibo Observatory in Puerto Rico collapses as engineers feared

Arecibo Observatory in Puerto Rico collapses as engineers feared


The telescope’s 900-ton platform came crashing down overnight

Share this story

The Arecibo Observatory prior to the collapse. The 900-ton platform suspended above the dish fell overnight.
Photo by Ricardo Arduengo / AFP via Getty Images

The massive Arecibo Observatory in Puerto Rico collapsed in on itself overnight. The catastrophic failure had been predicted by engineers after the telescope suffered two major cable malfunctions over the last couple of months, risking the integrity of the observatory’s entire structure.

Pictures of Arecibo surfaced online this morning, revealing that the massive 900-ton platform that is normally suspended above the observatory was no longer there. The National Science Foundation (NSF), which oversees Arecibo, confirmed to The Verge that the platform did come crashing down onto the telescope’s giant 1,000-foot-wide dish. No injuries have been reported, according to the agency.

“We are saddened by this situation but thankful that no one was hurt,” Sethuraman Panchanathan, the director of NSF, said in a statement. He added: “Our focus is now on assessing the damage, finding ways to restore operations at other parts of the observatory, and working to continue supporting the scientific community, and the people of Puerto Rico.”

This catastrophic scenario is something the NSF feared might happen. On November 19th, the agency announced that the remaining cables at Arecibo ran the risk of failing, which could lead to the platform’s collapse. Knowing this was imminent, NSF said it planned to demolish Arecibo in a controlled manner, concluding that there was no safe way to save the observatory. Managers had evacuated the facility and set up a “safety exclusion zone” to keep people away.

Local officials will make sure the area remains cleared, so that engineers can assess the extent of the damage, according to the NSF. The agency says it is trying to figure out how the fall occurred. Early assessments suggest that the top sections of all three towers holding up the massive platform broke away, causing the structure to fall. The telescope’s support cables also fell when the platform crashed, causing major damage to Arecibo’s nearby learning center. In a press conference in early November, the NSF noted that the main cables each weigh about 15,000 pounds.

The collapse comes at the end of a difficult period for Arecibo. In August, the observatory suffered its first major malfunction, when an auxiliary cable came loose from its socket and fell onto the observatory’s dish, punching a large hole in the structure. At the time, NSF and the University of Central Florida (UCF), which oversees day-to-day operations at Arecibo, vowed to investigate the failure and fix the damage in order to get the observatory up and running again.

But as engineers were figuring out a path forward for repairs, a second main cable failed on November 6th. This time, the cable snapped and also fell onto Arecibo’s giant dish, causing damage to other cables nearby. Engineers found that the other cables could not be guaranteed to hold. The NSF concluded that Arecibo would eventually collapse if no actions were taken; they just didn’t know when the collapse might occur. The agency had hoped to demolish the structure before it took place.

Damage to the Arecibo Observatory is seen on November 19th after the second cable failure.
Photo by Ricardo Arduengo / AFP via Getty Images

The NSF’s decision to tear down Arecibo was met with a lot of pushback from fans of the telescope. Arecibo has been a major beacon of opportunity in Puerto Rico as well as an incredible asset for peering into the cosmos. The observatory has been used to identify distant exotic objects like pulsars, as well as to listen for mysterious blasts of radio waves coming from the distant Universe. Scientists also used Arecibo in 1974 to send out a picture message out into the cosmos, detailing humanity’s achievements for anyone who might be listening. Arecibo has also made numerous cameos in television and film, including GoldenEye and Contact.

Not wanting to see the observatory demolished, a Puerto Rican scientist launched a petition on to urge the NSF to repair Arecibo. As of today, the petition has more than 36,000 signatures.

NSF says that engineers arrived at the site today, and it hopes to have personnel at the observatory tomorrow to figure out the environmental impact of the collapse. In the meantime, NSF says it will continue to authorize UCF to pay Arecibo’s staff and the agency will strive to do any remaining research and repairs that it can at the facility.

Update December 1st, 1:50PM ET: This story was updated to include information from an NSF press release.