Arecibo radio telescope goes dark after cutting cable-painted dish | Science

By Daniel Clery12 August 2020, 3:25 p.m.

The iconic Arecibo radio telescope in Puerto Rico was damaged on Tuesday morning, August 10, when a cut steel cable hit one of its antennas and shot a 30-meter hole in its 307-meter-wide dish. Observations have been halted for at least 2 weeks while research is being conducted, says Ramon Lugo, director of the Florida Space Institute at the University of Central Florida (UCF), which manages the observatory for the National Science Foundation (NSF). “My primary focus at the moment is the safety of people and the facility,” he says. The accident happened at 2:45 a.m., he says, but if it had been the day when more personnel were on the scene, there could have been injuries.

For nearly 60 years, Arecibo has been a mainstay of radio astronomy, atmospheric research, and planetary science. For decades, it was the main telescope used in the search for foreign intelligence. The dramatic appearance has won it as supporting roles in several films. The solid dish, built in a natural depression in the surrounding hills, was the largest single dish in the world until 2016, when it was taken over by China’s Five Hundred Meters Aperture Spherical Radio Telescope (FAST). Arecibo can only look straight up, but some steering is possible by moving the receivers, like antennas, around a platform suspended by cables high above the dish.

The cable that broke this week was not one of the main support cables, but one of several auxiliary languages ​​added in the 1990s to stabilize the platform when a large new antenna, known as the Gregorian dome, was added . The cable failed where it was on the platform. Because it contained a lot of stored energy from voltage, it fluttered wildly, damaging the Gregorian dome and the main reflector of the dish, Lugo says. The platform itself appears to be twisted, he adds.

Typically, such cables are not missing in that way, as far as “concerns” are concerned, he says. ‘We do not know why it happened. … It is thought that recent weather and seismic events may have contributed. The telescope suffered some damage from Hurricane Maria in 2017, but Lugo says it does not look like the two events are connected now. If it turns out to be a manufacturing defect, they will have to examine the other auxiliary cables. Until investigation is complete, Lugo could not say how much the repairs would cost or how long they would take. It could be anywhere from days to months, he says.

Arecibo’s status has been secure in recent years. Scientific interest has diminished as newer facilities come online, and NSF has sought to use its funding for new projects. In 2018, UCF took over the management of the facility in a deal that allowed NSF to reduce its investment. However, this new blow, on top of Hurricane Maria, is likely to reopen the debate over Arecibo’s future. “There are some sections of the population that will start that conversation,” Lugo says. “We need to stay focused on the ultimate goal of returning to full capacity.”