The National Science Foundation (NSF) will shut down Arecibo’s gigantic wireless dish after making the attached damage too severe to repair. Announced today (November. 19).
The announcement came as scientists await a verdict on the fate of the iconic observatory after the intricate cables supporting a 900-ton science platform were damaged above the plate.. . In August, a cable slipped out of its socket, but engineers assessing the situation deemed it stable.Earlier this month, a second cable unexpectedly broke off, making Arecibo’s fate all the more dangerous.. After looking at three separate engineering reports, NSF, which owns the property, determined that the facility is not stable enough that there is no way to repair the damage that does not expose individuals to undue risk..
“Our goal was to find a way to preserve the telescope without endangering anyone’s safety,” Shawn Jones, assistant director of the Directorate of Mathematical and Physical Sciences at the National Science Foundation, said at a press conference today. « However, after receiving and reviewing the engineering evaluations, we found no way forward that would allow us to do so safely.. We know that late decision-making leaves the entire facility at risk of uncontrolled collapse, putting people unnecessarily at risk as well as additional facilities..
« The telescope is currently at risk of an unexpected and uncontrolled collapse, » said Ralph Jaum, director of the Department of Astronomy at the National Science Foundation.. “According to engineering assessments, even attempted installation or cable testing may speed up catastrophic failure. Engineers can’t tell us the safety margin of the structure, but they have advised NSF that the structure will collapse in the near future on its own..
Although NSF is the agency most closely associated with the facility, NASA currently provides about a third of the observatory’s operating costs to fund planetary radar observations, especially near-Earth asteroids.. « While NASA was not directly involved in the investigation into the damage to the observatory in August, NSF engaged with stakeholders, including NASA, as the investigation was continuing, » NASA representatives wrote in a statement.. . « NASA respects the National Science Foundation’s decision to place the safety of those who work, visit, and study at the Historic Observatory above everything else..
During the press conference, officials emphasized that the decision was based on prioritizing safety, not a reflection of the scientific work Arecibo has done over the past decades or it could continue to do in the future, and that some hope the science will be lost with the facility.
« This decision has nothing to do with the scientific merits of Arecibo, » Gaume said.. « This is not a consideration. It’s all about safety.
Guame added that the agency would work with scientists who were planning to use the Arecibo Telescope and its other facilities in order to move those planned research projects wherever possible.. However, the facility was unique, particularly in its ability to radar, which was used extensively to study near-Earth asteroids and other solar system bodies..
Officials also asserted that if they manage to shut down the telescope in a controlled manner, the other assets in the Arecibo Observatory – primarily, the visitor center, the on-site atmospheric science instrument and the second atmospheric instrument on the neighboring island of Culebra – should survive.
Both failed Arecibo cables were connected to the same support tower. An engineering analysis completed after a second cable failure in November found that if another cable on this tower, dubbed Tower 4, failed, the platform would collapse into the dish and potentially cause the towers to collapse.. And because the cable support system is already fragile, engineers saw no way to safely assess the situation in more detail, let alone its stability..
“What we are facing is a structure whose margins of safety we do not understand. Engineering methods to better understand safety margins carry significant risks, and the engineering approach to fixing the structure appears to be extremely insecure.
This means that the situation is volatile enough that NSF cannot guarantee that the telescope will be turned off in a controlled manner. Gaume and Ashley Zauderer, Arecibo Observatory Program Director at NSF, said the agency had hired engineers to develop a plan for a controlled decommissioning. They added that creating that plan and collecting the necessary approvals for it will take several weeks.
Officials also refused to provide an idea of what this strategy would look like, although they mentioned the possibility of having helicopters or explosives in mind..
In conjunction with the press conference, NSF presented an engineering report from the company leading the analysis of the Arecibo Telescope after the second failure, which provides few details about the facility’s fate..
“We believe the structure will collapse in the near future if left untouched,” John Abruzzo, managing director of Thornton Tomasetti, wrote,. « Controlled demolition, designed with a specific breakdown sequence that is identified and executed with explosives, will reduce the uncertainty and risk associated with the breakdown..
The seriousness of the situation stems from the fact that Kaplan had already failed, and the way three separate engineering consultants were caught by surprise by the second failure.. « The three expert companies we brought in provided no input or any idea there was a problem, » Gome said of the main cables after the August failure.. .
“I think it’s really unfortunate that this major cable failed before we had a chance to stabilize things,” Zoderer said..
NSF officials said that currently, their priority is to safely turn off the radio dish and protect as much of other facilities on site as possible. But they assured that they are not decommissioning the Arecibo observatory as a whole, that they understand the importance of the facility in Puerto Rico, and that they want in the long term to guarantee the future of the site and the science it has adopted for decades. .
“We are discussing decommissioning a structure made of steel and cable, but the people who work in this field really have the ideas,” said Zuderer. “The idea of discovery is what triggered the construction, it is the passion of the people who work in the observatory . . . To continue exploring and learning, this is the true heart and soul of Arecibo.
Editor’s note: This story has been updated to include NASA’s statement about the fate of the Arecibo telescope. Send an email to Meghan Bartels at mbartels @ space. com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.
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Arecibo Observatory, Radio Telescope, Telescope, National Science Foundation, Observatory, Astronomy
World News – United States – The Arecibo Radio Telescope, a symbol of astronomy, is missing
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