Comment by metalman
1 day ago
not good, not good at all, as this is how ALL bridges and towers are supported, the basic engineering bieng that any cable end will be stronger than the cable itself and will last longer than the cable itself, except now, when it isn't, not good, not easy to inspect, not easy to service.
> Long-term low-current electroplasticity, induced by the electromagnetic waves from the Arecibo telescope itself, may have sped up the zinc creep, it says.
I presume we aren't using most bridges as interstellar antennas.
The main paper goes into the detail on page 2. The cables were on beam path.
“The only hypothesis the committee could develop that provides a plausible but unprovable answer to all these questions and the observed socket failure pattern is that the socket zinc creep was unexpectedly accelerated in the Arecibo Telescope’s uniquely powerful electromagnetic radiation environment. The Arecibo Telescope cables were suspended across the beam of “the most powerful radio transmitter on Earth. National Academies of Sciences, Engineering, and Medicine. 2024. Failure Analysis of the Arecibo Observatory 305-Meter Telescope Collapse. Washington, DC: The National Academies Press. https://doi.org/10.17226/26982.”
> I presume we aren't using most bridges as interstellar antennas.
any like area of metal will receive as much interstellar emissions but I guess they did run a MW transmitter sometimes.
MW as in Mega Watts? (I read it as Medium Wave the first time)
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Arecibo didn’t know it was a telescope. Every wire in the world is an antenna.
No, but there is a lot of potential for large structures to act like an accidental antenna and/or receive low level voltages from the environment or other equipment.
Likely won't matter in most cases, but there could be a few disasters waiting around.
That’s what the government (… and most rational people) wants you to think.
how could the government control the birds without using bridges as antennas?!
My guess is the safety factor here was lower than typical, causing the failure mode to occur.
I expect future bridges will design these joints even more conservatively because they were skating closer to the edge than they realized.
They also mentioned that this is the first example of the unknown phenomena that caused the creep. This technology has been in use quite successfully for more than 100 years.
Bridges probably shouldn't be subject to the same electromagnetic radiation that gets focused by the telescope though so ideally not a problem there.
Where the cables were there’s nothing focused, just wires, it was outside of the dish.
They were across the dish. From the report: “The Arecibo Telescope cables were suspended across the beam of “the most powerful radio transmitter on Earth””
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This would predict that we should be seeing far more mystery collapses than we do though