A very good, fairly long article in Science Magazine, linked below, on how and why Arecibo fell, and what, if anything, might be built in its place. To summarize:

Several factors probably lead to the collapse, including poor workmanship in attaching support cables to their sockets. Narrow load safety factors in the cabling -- only about 1/3 of that in a somewhat comparable structure like a suspension bridge. The increased weight of the added-on Gregorian dome and antennas.

The proposed replacement is interesting -- a multitude of 9-meter dishes, fixed to a rigid platform extended across the depression in which the original dish sat. The entire structure would tilt to allow a greater part of the sky to be observed, than before.

https://www.sciencemag.org/news/2021/01/how-famed-arecibo-telescope-fell-and-how-it-might-rise-again

https://www.sciencemag.org/news/2021/01/how-famed-arecibo-telescope-fell-and-how-it-might-rise-again

This just blew my mind. I had to idea the amount of damage caused.

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~ Life's short; make fun of it.
User ID: 39750; SETI@home member since: 5 May 1999; Classic workunits: 5,851; Classic CPU time: 108,169 hours

A good find there John.
Quite an eye opening read, some I already knew, but quite a bit of stuff new to me.
It certainly strikes me that there were a number of corners cut at just about every sage along the dish's life between construction and the middle of 2020. It certainly underlines all the difficulties that were being faced in the months leading up to the final failure, not the least of which was the rate of strand failure - I've not done the sums, but a strand failing just about every day for the last year is a lot of residual strength being eroded; to such an extent that there was probably only a maximum life expectancy of of a couple of years the main cables.

That suggestion for a massive flat plate reflector is certainly in the spirit of the old dish - big and a step into the unknown, but using existing technologies scaled up to the nth degree. I'd love to see that idea being developed a bit further to get some idea of the mass and forces required.

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Bob Smith
Member of Seti PIPPS (Pluto is a Planet Protest Society)
Somewhere in the (un)known Universe?

On August 14 2018 the Morandi bridge in Genoa failed with the loss of 43 people. The failure was due to corroded cables that were not monitored and substituted in time. There is a process going on with charges of manslaughter to the firm which built and maintained the bridge, gaining a lot of money because the autostrada which runs on it is a toll road. Now a new bridge, designed by Renzo Piano, has been built in less that two years and is based on steel pylons in the salty air of Genoa.
Tullio

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Arecibo replacement could support space situational awareness
By Jeff Foust — January 22, 2021, SPACENEWS

https://spacenews.com/arecibo-replacement-could-support-space-situational-awareness/

Here's a recent Physics World Podcast:

Arecibo Observatory: a scientific giant that fell to Earth
wrote:

1 December 2020 was a dark day for Puerto Rico and the global astronomy community. The iconic Arecibo Observatory collapsed, with the radio telescope’s 900-tonne suspended platform crashing into the 305?m dish below. Warning signs had been there in the preceding months, but that did little to soften the shock felt by the astronomy community.

In this episode of the Physics World Stories podcast, Andrew Glester speaks with astronomers about the impact...

... Arecibo’s size and tropical setting captured the public imagination and the observatory appeared in the films GoldenEye and Contact – the adaptation of the Carl Sagan novel. Contact’s lead protagonist is Ellie Arroway (played by Jodie Foster), partly based on SETI scientist Jill Tarter. Tarter joins the podcast recounting her experiences advising Jodie Foster on the character and role.

Keep searchin'!
Martin

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See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

Message 2055672 wrote:

...funding to "Make Arecibo Great Again"!

Indeed so!


Here we have a proposal to make Arecibo bigger and better...

On the far side of the moon!


MOONBASE Project - Prof Simon



Keep searchin'!
Martin

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See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

Scientists want to build a new, very different Arecibo Telescope to replace fallen icon.
By Meghan Bartels - July 22, 2021, Space.com

https://www.space.com/arecibo-telescope-replacement-process-and-designs

A replacement for Arecibo planetary radar with better resolution?

Tycho Crater of the Moon Revealed in Intricate Detail: Powerful new radar technology will reveal the secrets of the solar system.

https://remonews.com/canada/tycho-crater-of-the-moon-revealed-in-intricate-detail-powerful-new-radar-technology-will-reveal-the-secrets-of-the-solar-system/

Arecibo Observatory: A year after telescope's collapse, an icon gets continuing cleanup and a new documentary.

By Meghan Bartels, 1 DEC 2021, Space.com.

https://www.space.com/arecibo-radio-telescope-collapse-anniversary

Arecibo Observatory reopens visitor center after telescope collapse

March 11 (UPI) -- The famous Arecibo Observatory in Puerto Rico, once home to the world's most powerful radio telescope, has reopened to visitors more than a year after the giant facility collapsed.

The visitor center and observation deck are now open to visitors who make reservations in advance. From the outdoor deck, visitors can see the valley and remaining reflective dish -- 1,000 feet in diameter.

Visitors began signing up for tours as soon as Arecibo announced it would reopen Wednesday, said Ricardo Correa, director of communications.

"People thought we were going to be closed forever because we lost the big instrument. To their surprise, they are seeing that science is still ongoing here," Correa said. "Arecibo is not closed anymore."

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A new role for Arecibo.

Site of Collapsed Arecibo Telescope Will Become an Education Center.

The National Science Foundation announced this week that the site of the destroyed Arecibo Observatory radio telescope in Puerto Rico will become a STEM-focused educational center, and it’s seeking proposals to manage the new project.

According to an NSF release, the center will expand on existing educational programs at the Arecibo Observatory and would open in 2023....

Cheers.

Some stills and stories

https://www.space.com/arecibo-observatory-radio-telescope-collapse-photos

Videos and more stories https://www.space.com/arecibo-observatory-collapse-drone-video-nsf-evaluation

This happened Dec 2020 but I assume it contributed to closing SETI

Arecibo telescope might have failed because of weak sockets

The collapse of the 305-meter telescope at Arecibo Observatory in 2020 is being attributed to zinc creep – slow deformation due to stress – in the telescope's cable spelter sockets, according to a committee report from the National Academies of Sciences, Engineering, and Medicine.

This effect may also have been accelerated by the effect of low-level electric current on the structure of zinc – a phenomenon known as electroplasticity.

Is that some 'euphemism' for electrolytic corrosion due to dissimilar metals in a damp environment? A process that is accelerated by electric current... As can be expected for large structures in Earth's magnetic field... And especially so for high powered transmitters such as the Arecibo interplanetary radar...


Also, were not those areas protected by equipment that ensured dry air always flowed through the support cables to prevent corrosion... Until cost cutting cut the funding...


Accountants, vs Science and good safe engineering?


Keep searchin'?
Martin

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See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)