Huge Radio Telescope Collapses The Arecibo Observatory's 900-ton receiver platform fell onto the reflector dish more than 400 feet below. Dec 1st, 2020 Danica Coto Satellite image of the damaged radio telescope at the Arecibo Observatory in Puerto Rico, Nov. 17, 2020. Maxar Technologies via AP SAN JUAN, Puerto Rico (AP) — A huge, already damaged radio telescope in Puerto Rico that has played a key role in astronomical discoveries for more than half a century completely collapsed on Tuesday. The telescope's 900-ton receiver platform fell onto the reflector dish more than 400 feet below. The U.S. National Science Foundation had earlier announced that the Arecibo Observatory would be closed. An auxiliary cable snapped in August, causing a 100-foot gash on the 1,000-foot-wide (305-meter-wide) dish and damaged the receiver platform that hung above it. Then a main cable broke in early November. The collapse stunned many scientists who had relied on what was until recently the largest radio telescope in the world. “It sounded like a rumble. I knew exactly what it was,” said Jonathan Friedman, who worked for 26 years as a senior research associate at the observatory and still lives near it. “I was screaming. Personally, I was out of control.... I don't have words to express it. It's a very deep, terrible feeling.” Friedman ran up a small hill near his home and confirmed his suspicions: A cloud of dust hung in the air where the structure once stood, demolishing hopes held by some scientists that the telescope could somehow be repaired. “It's a huge loss,” said Carmen Pantoja, an astronomer and professor at the University of Puerto Rico who used the telescope for her doctorate. “It was a chapter of my life.” Scientists worldwide had been petitioning U.S. officials and others to reverse the NSF's decision to close the observatory. The NSF said at the time that it intended to eventually reopen the visitor center and restore operations at the observatory’s remaining assets, including its two LIDAR facilities used for upper atmospheric and ionospheric research, including analyzing cloud cover and precipitation data. The telescope was built in the 1960s with money from the Defense Department amid a push to develop anti-ballistic missile defenses. It had endured hurricanes, tropical humidity and a recent string of earthquakes in its 57 years of operation. The telescope has been used to track asteroids on a path to Earth, conduct research that led to a Nobel Prize and determine if a planet is potentially habitable. It also served as a training ground for graduate students and drew about 90,000 visitors a year. “I am one of those students who visited it when young and got inspired,” said Abel Méndez, a physics and astrobiology professor at the University of Puerto Rico at Arecibo who has used the telescope for research. “The world without the observatory loses, but Puerto Rico loses even more.” He last used the telescope on Aug. 6, just days before a socket holding the auxiliary cable that snapped failed in what experts believe could be a manufacturing error. The National Science Foundation, which owns the observatory that is managed by the University of Central Florida, said crews who evaluated the structure after the first incident determined that the remaining cables could handle the additional weight. But on Nov. 6, another cable broke. A spokesman for the observatory said there would be no immediate comment, and a spokeswoman for the University of Central Florida did not return requests for comment. Scientists had used the telescope to study pulsars to detect gravitational waves as well as search for neutral hydrogen, which can reveal how certain cosmic structures are formed. About 250 scientists worldwide had been using the observatory when it closed in August, including Méndez, who was studying stars to detect habitable plantes. “I'm trying to recover,” he said. “I am still very much affected.”
Apparently, the 305-foot telescope platform collapsed this morning December 1st. Here is a link to the NSF article. https://www.nsf.gov/news/news_summ.jsp?cntn_id=301737 73 de Chuck W3oN
Hmm... Perhaps it is time for a high tech replacement using that same real estate. Are there any plans for the current site? Recycle everything first.
Today the dome collapsed, the observatory was almost completely destroyed. Since 1962 it was the largest radio telescope in the world. Today this colossus dies.
Apparently Colossus still has LOTS to teach to students in the field of Mechanics. Not as a noble as Radio-Astrophysics sure! Might AO wreckage spark Surveyors, Cargo Planners, Heavy Lift Engineers successful careers.
Computational Physicist Scott Manley discusses failure modes of the AO, and reveals that an earthquake in the Dominican Republic may have triggered the collapse. Airborne footage from a plane this morning.
From that article 60%. Wow. Did that cable that broke a few weeks ago date back to the beginning ? 57 years old? Assuming that the cables started out within specifications, that's a 40% degradation over 57 years. That seems like a huge number. Since this seems to have taken everyone by surprise, it either means there has been slow cumulative deterioration over the long term that nobody noticed, or some new unexpected runaway failure mode kicked in that led to a very large degradation over a short term, that nobody noticed. Either way, nobody noticed. If they had, they could have extended the life considerably by reducing the loads, instead of adding more and more stuff. Eventually there will be some sort of failure investigation report. It will be interesting. Anyone want to bet that they'll find a way to blame it on "climate change" ? It is NSF, after all.
Back a few posts KW1NG put up the recent AP article that said of the event that started the dominoes toppling, "... a socket holding the auxiliary cable that snapped failed in what experts believe could be a manufacturing error. " Wonder if that's worth any legal recourse to recover damages? Waiting for the VE7 to claim the "RF-Seismograph" detected not only the Domincan trembor, which of course caused the surge in propagation last weekend (not the sun spot) but also predicted the dish implosion, as it focused and reflected natural RF off the ionosphere.
WP3R discussing the collapse....go down just a little for the video.... https://twitter.com/i/status/1333835086429638658
From the Puerto Rico Seismic Network (PRSN); "The Puerto Rico Seismic Network (PRSN) is saddened to learn about the collapse at the Arecibo Radiotelescope Observatory this morning of December 1st, 2020. PRSN’s seismic station AOPR, located within the premises of the observatory, detected the timing of the failure. This seismic station has been a long collaboration between PRSN and the Arecibo Observatory. Here we publish the seismic record of AOPR at the time of collapse, which coincidentally occurred during the passage of seismic waves through Puerto Rico from a Dominican Republic earthquake of M4.0 that occurred at 07:51 AM AST. The figure below shows 07:52:42 AM AST (11:52:42 UTC) as the exact time of collapse at the AOPR seismic station, denoted by a sharp impulsive signal, right after the arrival of the S wave of the earthquake. It is a sad day for Science and a tragedy to lose such an important, iconic, valuable, and unique scientific instrument and allowed so many scientific advances and discoveries to humanity." https://www.facebook.com/redsismicadepuertorico
I think this seismic event was the kind that caused a radio blackout. At least at the frequencies used by the observatory.
Well, certainly there is THAT. NO DOUBT the frequencies AO once monitored are a thing of that antenna's past. You may be unaware of a proponent of "seismic activity causes propagation on HF" to which I was referring Dave W7UUU
