After cables holding the 900-tonne receiver above the reflector dish snapped late last year, first in August and then in November, engineers could not figure out a way to fix the damage in a safe manner that would not already accelerate the collapse of the weakened structure. Subsequently, the US National Science Foundation (NSF), the public body responsible for Arecibo, announced two weeks ago that the telescope would be decommissioned.
In a foreboding quote from the announcement, Ralph Gaume, director of the astronomy division at the NSF, said, “Even attempts at stabilization or at testing the cables could result in accelerating the catastrophic failure.” Merely two weeks later, this became a reality: more cables failed, and the receiver came crashing down, directly onto the reflector dish 127m below. Fortunately, nobody was injured due to the collapse.
The diameter of the dish is 305 meters
Dr David Clements, an Imperial astrophysicist who recently helped make headlines with the discovery of phosphine on Venus, said to the New Scientist: “It’s a sad end to a spectacular telescope, the amazing instrument has been involved in all sorts of things.”
At its opening in 1963, Arecibo was the world’s largest single-dish radio telescope, holding the title for more than 50 years. Throughout its life, it gathered data for some of the most important astronomical discoveries, from neutron stars to exoplanets. In 1974, it sent out a radio signal which contained one of humanity’s first messages aimed at extra-terrestrials.
The telescope had a dish diameter of 305m, and so was superseded in size by China’s Five-hundred-metre Aperture Spherical Telescope (FAST). However, astronomers insist that Arecibo is irreplaceable, with #WhatAreciboMeansToMe trending on Twitter in astronomy and physics circles. For many Puerto Rican scientists, Arecibo was a source of pride. Puerto Rican writer Andrea González-Ramírez tweeted: “A rite of passage for most Puerto Rican kids was visiting El Observatorio de Arecibo during school trips. This is a devastating loss for the island and the scientific community.”