(China’s 500-meter Aperture Spherical Telescope (FAST), which opened in 2016, does not currently have the ability to do such radar studies.) Not having it “will be a big loss”, says Alan Harris, an asteroid scientist in La Canada, California. The telescope pinged radio waves at near-Earth asteroids to reveal the shape and spin of these threatening space rocks. The science that has ground to a halt includes Arecibo’s world-leading asteroid studies. There is no estimate yet for the cost of decommissioning the telescope. The ageing structure has suffered other shocks in recent years, including damage to an antenna and the dish caused by Hurricane Maria in 2017. Zauderer said that maintenance in recent years had been completed according to schedule.īefore this year, the last major cable problems at the observatory were in January 2014, when a magnitude-6.4 earthquake caused damage to another of the main cables, which engineers repaired. Over the years, external review committees have highlighted the ongoing need to maintain the ageing cables. Credit: University of Central Florida/Arecibo Observatoryīut that main cable, which was installed in the early 1960s, had apparently degraded over time. The main cable that failed experienced wire breaks (shown) before its sudden and unexpected collapse. “It was not seen as an immediate threat,” says Ashley Zauderer, programme director for Arecibo at the NSF.
After the first, engineering teams spotted a handful of broken wires on the second cable, which was more crucial to holding up the platform, but they did not see it as a major problem because the weight it was carrying was well within its design capacity. NSF officials insist that the cable failures came as a surprise. “Losing the Arecibo Observatory would be a big loss for science, for planetary defence and for Puerto Rico,” said Desireé Cotto-Figueroa, an astronomer at the University of Puerto Rico Humacao, in an e-mail before the closure was announced. A social-media campaign with the hashtag #WhatAreciboMeansToMe sprung up almost immediately, with astronomers, engineers and other scientists - many from Puerto Rico - sharing stories of how the observatory had shaped their careers. The closure comes as a shock to the wider astronomical community. “This decision is not an easy one to make, but safety is the number-one priority,” said Sean Jones, head of the NSF’s mathematical and physical sciences directorate. So the NSF decided to close the Arecibo dish permanently. Why ultra-powerful radio bursts are the most perplexing mystery in astronomy These are some of the only public glimpses of the damage so far. A second photograph, released this week by observatory officials, also reveals the destruction.
The first cable slipped out of its socket and smashed panels at the edge of the dish, but the second broke in half and tore huge gashes in a central portion of the dish.Ī high-resolution satellite image, produced at Nature’s request by Planet, an Earth-observation company based in San Francisco, California, shows the extent of the damage wrought by the second cable: the green of the vegetation below shows through large holes in the dish. The cables that broke helped to support a 900-tonne platform of scientific instruments, which hangs above the main telescope dish. All those lines of investigation have now been shut down for good, although limited science will continue at some smaller facilities on the Arecibo site.
It has also done pioneering work in exploring many phenomena, including near-Earth asteroids and the puzzling celestial blasts known as fast radio bursts. It was the site from which astronomers sent an interstellar radio message in 1974, in the hope that any extraterrestrials might hear it, and where the first confirmed extrasolar planet was discovered, in 1992. The Arecibo telescope, which was built in 1963, was the world’s largest radio telescope for decades and has historical and modern importance in astronomy. “I am totally devastated,” says Abel Méndez, an astrobiologist at the University of Puerto Rico at Arecibo who uses the observatory. Arecibo telescope wins reprieve from US government
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