The legendary radio telescope at the Arecibo Observatory in Puerto Rico has collapsed, leaving astronomers and the Puerto Rican science community to mourn its destruction.
Engineers cautioned that the 900-ton structure, which was suspended above the 305-meter-wide dish of the telescope, could collapse at any point, provided that one of the main cables supporting it had broken in early November. Last month, the U.S. National Science Foundation (NSF), which owns the observatory, declared that it would completely shut down the telescope, citing safety issues about its instability and damage that was too severe to restore.
The final fall occurred shortly before 8 a.m. local time on Dec. 1. No one has been injured.
A drone video of the collapse, released two days later by the NSF, shows cables snapping at the top of one of the three towers from which the instrument platform was suspended. The platform plummets down and falls into the side of the dish. The tops of the three towers snap off too.
Prior to the fall, engineers were investigating ways to ease some of the strain in the cables, including by relaxing other support cables to tilt the towers around the dish. The NSF had not yet agreed to go on with the proposal when the platform collapsed.
Any of the nearby buildings, including the control room and the visitor center, survived the collapse. However, an educational facility seems to have been substantially destroyed by the crashing platform and cables.
Questions exist as to whether the cables have been properly maintained over the years. The cable that collapsed in November, precipitating the final fall, dated back to the building of the observatory in 1963.
Once the world's largest single-dish radio telescope, the Arecibo facility has been the site of several key astronomical discoveries over the years, including observations of spinning stars known as pulsars that contributed to the 1993 Nobel Prize in Physics. Before its failure, scientists used the telescope for a variety of observational experiments, including radar measurements of near-earth asteroids, to measure their danger to Earth.
The NSF says that it will continue to pay staff at the observatory and carry on with science at its smaller on-site locations that do not include the 305-meter dish. It is not clear whether the dish will be destroyed, restored, or left in ruins, as it is.
Observatory director Francisco Córdova told reporters that officials will explore ways to develop comparable or perhaps better scientific capabilities, maybe at or near the site. However, this will rely on the US Congress to allocate money to replace the Arecibo dish.
Ralph Gaume, director of the NSF astronomy department, said at a press conference on Dec. 3 that any replacement would be a multi-year project requiring congressional funding and the consideration of the needs of the science community.
