The Arecibo Observatory, a huge and previously damaged radio telescope in Puerto Rico that played a key role in astronomical discoveries for more than half a century, completely collapsed on Tuesday.
The telescope's 900-ton receiver platform fell onto the reflector dish more than 400 feet below.
Puerto Rican meteorologist Ada Monzón broke into tears on local TV as she delivered the devastating news to other heartbroken Puerto Ricans across the U.S. territory.
"I have to inform you, with my heart in hand, that the Arecibo Observatory collapsed," she said in Spanish. "We made every attempt to save it."
The U.S. National Science Foundation had earlier announced that the Arecibo Observatory would be closed. An auxiliary cable snapped in August, causing a 100-foot gash on the 1,000-foot-wide (305-meter-wide) reflector dish and damaged the receiver platform that hung above it. Then a main cable broke in early November.
No injuries were reported as a result of the Arecibo Observatory collapse, according the NSF.
"NSF is saddened by this development. As we move forward, we will be looking for ways to assist the scientific community and maintain our strong relationship with the people of Puerto Rico," the organization tweeted.
The collapse stunned many scientists who had relied on what was until recently the largest radio telescope in the world.
Dr. Jonathan Friedman, a scientist who worked in the Arecibo Observatory for half his life, told WAPA-TV in Puerto Rico that the collapse felt like 'an avalanche."
"At first, I thought it was one of the earthquakes that we felt in January. It sounded like a train or an avalanche. The rumble lasted a few seconds," said Friedman in Spanish.
“It's a huge loss,” said Carmen Pantoja, an astronomer and professor at the University of Puerto Rico who used the telescope for her doctorate. “It was a chapter of my life.”
Meteorologist Deborah Martorell told Puerto Rican national newspaper El Nuevo Día she visited the Arecibo Observatory Monday not knowing it would be her last time.
“There is a lot of anger in the scientific community because it could have been avoided. The bureaucracy and waiting around for NSF destroyed the platform of the Arecibo Observatory," she said in Spanish. “It is very difficult to think that I was there and saw how beautiful it was. It was a jewel of science ... It is very difficult to believe."
Scientists worldwide had been petitioning U.S. officials and others to reverse the NSF's decision to close the observatory. The NSF said at the time that it intended to eventually reopen the visitor center and restore operations at the observatory’s remaining assets, including its two LIDAR facilities used for upper atmospheric and ionospheric research, including analyzing cloud cover and precipitation data.
Wilbert Andrés Ruperto, vice president of Students for the Exploration and Development of Space, a student organization at the University of Puerto Rico in Mayagüez, has been advocating for the preservation of the Arecibo Observatory after starting a social media movement to #SaveTheAreciboObservatory.
"Here is the view of The Arecibo Observatory. A sad day for science, for Puerto Rico, and for the entire world. We will not rest until we #RebuildAreciboObservatory. Now we will fight faster and stronger. We can’t lose our Observatory forever," he tweeted.
The telescope was built in the 1960s with money from the Defense Department amid a push to develop anti-ballistic missile defenses. It had endured hurricanes, tropical humidity and a recent string of earthquakes in its 57 years of operation.
The telescope has been used to track asteroids on a path to Earth, conduct research that led to a Nobel Prize and determine if a planet is potentially habitable. It also served as a training ground for graduate students and drew about 90,000 visitors a year.
“I am one of those students who visited it when young and got inspired,” said Abel Méndez, a physics and astrobiology professor at the University of Puerto Rico at Arecibo who has used the telescope for research. “The world without the observatory loses, but Puerto Rico loses even more.”
He last used the telescope on Aug. 6, just days before a socket holding the auxiliary cable that snapped failed in what experts believe could be a manufacturing error. The National Science Foundation, which owns the observatory that is managed by the University of Central Florida, said crews who evaluated the structure after the first incident determined that the remaining cables could handle the additional weight.
But on Nov. 6, another cable broke.
A spokesman for the observatory said there would be no immediate comment, and a spokeswoman for the University of Central Florida did not return requests for comment.
Scientists had used the telescope to study pulsars to detect gravitational waves as well as search for neutral hydrogen, which can reveal how certain cosmic structures are formed. About 250 scientists worldwide had been using the observatory when it closed in August, including Méndez, who was studying stars to detect habitable planets.
“I'm trying to recover,” he said. “I am still very much affected.”