December 3, 2020


Aim for Excellence

Legendary Arecibo Telescope Will Close Forever, And Scientists Are Reeling

1 of astronomy’s most renowned telescopes—the 305-metre-vast radio telescope at Arecibo, Puerto Rico—is permanently closing....

1 of astronomy’s most renowned telescopes—the 305-metre-vast radio telescope at Arecibo, Puerto Rico—is permanently closing. Engineers can’t find a harmless way to repair it immediately after two cables supporting the structure suddenly and catastrophically broke, one particular in August and one particular in early November.

It is the finish of a single of the most iconic and scientifically effective telescopes in the background of astronomy—and researchers are mourning its decline.

“I really do not know what to say,” states Robert Kerr, a previous director of the observatory. “It’s just unbelievable.”

“I am thoroughly devastated,” states Abel Mendéz, an astrobiologist at the University of Puerto Rico in Arecibo who uses the observatory.

The Arecibo telescope, which was designed in 1963, was the world’s premier radio telescope for many years and has historic and fashionable value in astronomy. It was the web-site from which astronomers sent an interstellar radio information in 1974, in circumstance any extraterrestrials may well listen to it, and where by the very first acknowledged extrasolar earth was found out, in 1992. It has also accomplished pioneering function in detecting around-Earth asteroids, observing the puzzling celestial blasts acknowledged as quickly radio bursts, and researching quite a few other phenomena. All of individuals strains of investigation are now shut down for very good, although confined science continues at some smaller sized facilities at the Arecibo internet site.

Evaluating the injury

The cables that broke helped assistance a 900-tonne system of scientific devices, which hangs higher than the primary telescope dish. The first cable smashed panels at the edge of the dish, but the 2nd tore massive gashes in a central portion of it.A superior-resolution satellite image, produced at Character’s request by Earth, an Earth-observing enterprise, exhibits the extent of the destruction wrought by the second cable the green of the vegetation underneath exhibits via big holes in the dish. A second photograph, released this week by observatory officers, also reveals the destruction. They are the only public glimpses of the damage to day.

If any more cables fail—which could materialize at any time—the entire platform could crash into the dish down below. The US Nationwide Science Basis (NSF), which owns Arecibo Observatory, is doing work on strategies to safely reduce the system down in a managed vogue.

But those plans will take months to acquire, and there’s no telling regardless of whether the platform could possibly crash down uncontrollably in the meantime. “Even makes an attempt at stabilization or at screening the cables could outcome in accelerating the catastrophic failure,” reported Ralph Gaume, the NSF’s head of astronomy, at a 19 November media briefing.

So NSF made a decision to close the Arecibo dish forever. “This decision is not an effortless 1 to make, but safety is the range-just one precedence,” said Sean Jones, head of NSF’s mathematical and bodily sciences directorate.

The closure is probable to occur as a shock to the broader astronomical community. “Losing the Arecibo Observatory would be a large reduction for science, for planetary defense, and for Puerto Rico,” said Desireé Cotto-Figueroa, an astronomer at the College of Puerto Rico at Humacao, in an electronic mail prior to the introduced closure.

NSF officials insist that the cable failures came as a shock. Just after the initially, engineering teams spotted a handful of broken wires on the second cable, which was more very important to holding up the framework, but they did not see it as a main challenge due to the fact the fat it was carrying was perfectly within just its design and style capacity. “It was not noticed as an instant menace,” says Ashley Zauderer, programme manager for Arecibo at the NSF.

About the a long time, exterior review committees have highlighted the ongoing want to retain the telescope’s ageing cables. Zauderer claimed that maintenance had been accomplished according to schedule.

Just before this yr, the final big cable troubles at the observatory ended up in January 2014, when a magnitude-6.4 earthquake caused problems to another of the main cables, which engineers fixed. The ageing framework has experienced other shocks in new a long time, like Hurricane Maria in 2017 and a series of smaller sized earthquakes in January of this year.

There is no estimate yet on the expense of decommissioning the telescope.

A famous website

Some of the observatory’s scientific tasks may perhaps be in a position to be transferred to other facilities, Gaume said—and that he expects scientists to propose where by to shift their analysis to. Science does continue at other parts of the Arecibo observatory, which encompasses additional than the 305-metre dish. They contain two lidar facilities that shoot lasers into the environment to review atmospheric phenomena.

Arecibo experienced been frequently upgraded, with various new instruments slated to be set up in the coming yrs. “The telescope is in no way out of date,” claims Christopher Salter, an astronomer at the Countrywide Radio Astronomy Observatory in Inexperienced Bank, West Virginia, who labored at Arecibo for yrs.

The observatory is also a big science-academic centre for Puerto Rico, fostering the occupations of numerous astronomers and engineers. And it has come to be a part of the pop lifestyle lexicon, that includes in big motion pictures this sort of as Call, based on a Carl Sagan novel, and the James Bond film GoldenEye.

The previous major radio telescope disaster happened in 1988, when a 300-foot-wide antenna at the observatory in Inexperienced Lender, West Virginia, collapsed a person night owing to structural failure.

This report is reproduced with permission and was initially revealed on November 19 2020.