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Drone Footage of Arecibo Observatory Collapse

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Re: Drone Footage of Arecibo Observatory Collapse

#91

Post by masklinn »

awiesenhofer wrote: post #82

So if they knew there is no money to even maintain it and this collapse was a likely outcome why not lower the platform in advance before any cable breaks? Just from a safety perspective omitting this seems to be somewhat negligent, no?

I'm not sure it was possible, the cables were likely anchored (frayed then sunk in concrete), it would have required setting up a mobile anchor, cutting the cable from the anchor, adding lengths of cables somehow, and unspooling those extra lengths. It's already not done for suspension bridges[0], I don't think it could be done here.

And the risk would obviously have been gigantic as two cables had already snapped in the same place, so the remaining cables would be under insane and completely out of spec tensions, meaning they could fail at any point during the tentative transfer work.

[0] you either splay open the main cables and replace strands, or you need to jack the entire bridge from below to take down and replace the main cables at once

Re: Drone Footage of Arecibo Observatory Collapse

#92

Post by Tuna-Fish »

awiesenhofer wrote: post #82

So if they knew there is no money to even maintain it and this collapse was a likely outcome why not lower the platform in advance before any cable breaks? Just from a safety perspective omitting this seems to be somewhat negligent, no?

As it existed, it didn't have any of the equipment needed to lower it. It was raised to it's position with temporary equipment, then the cables that held it up were fixed in place, and then the temporary equipment was removed.

So to lower it, they'd have had to do a lot work adding stuff near the cables. Which they already knew to be a lot weaker than they were supposed to be, and of which two had already failed. That would have been the really negligent thing to do, instead of just removing all people from near the dish which was done.

Re: Drone Footage of Arecibo Observatory Collapse

#93

Post by libria »

usrusr wrote: post #77
yborg wrote: post #55

Earlier quoted context omitted.

And they must have known it was imminent, it seems unlikely they had a drone over it 24/7 given the available hover time.

For a use case like this, I'd imagine that tethered multicopters could be a very nice fit. If you can just plug the base station into a power outlet, suddenly 24/7 doesn't seem that crazy. PS: Apparently I'm not alone with this idea, search engine comes up with hits. https://elistair.com/ even have a tether kit you can plug into some DJI models (and others) instead of the conventional battery pack. Out of Lyon, Franc…

Bonus, if they tethered it to the suspended receiver, it would automatically follow the action right down to impact, albeit with unpredictable viewing angles.

Re: Drone Footage of Arecibo Observatory Collapse

#94

Post by keeganpoppen »

briancp wrote: post #27

Posted this in another thread, but there’s some neat photos from the 60s of the telescope under construction here: https://www.naic.edu/history_gal/historicgal.html Beyond the scientific value, it is (was) just a neat feat of engineering getting this built in the middle of the jungle.

wow those pics are incredible; must have been a hell of a sight to put up. although, i guess that's true of a lot of the public works-y sorts of things we did in the 40s-70s (not that this really technically counts, probably, but whatever).

Re: Drone Footage of Arecibo Observatory Collapse

#97

Post by Gibbon1 »

worker767424 wrote: post #80
solarkraft wrote: post #13

Wow. As tragic as the collapse is, at least it has been filmed (i thought it had not when I saw the announcement tweet with its far-away photo). If nothing else it's about as spectacular as I had expected. Had I been in the area I'd have been tempted to set up my camera somewhere close (remember that the risk of collapse was known to be high).

346 people dying in 737 MAX crashes is tragic. This is a 50-year-old telescope; the word I'd use is "unfortunate."

The two people I'm friends with that are in the field made sucks but good riddance noises about the collapse.

Re: Drone Footage of Arecibo Observatory Collapse

#98

Post by ars »

dylan604 wrote: post #41

So now, humans are going to be the intergalactic assholes of the universe who go and change their phone number without leaving a forwarding number. When our message sent from Arecibo is finally received, their response will go to a disconnected number. https://www.youtube.com/watch?v=2BVbyCZXc5s

That's an evocative way of writing, but I'm sure you know that Arecibo doesn't usually spend much time pointed in that direction, so there's no actual practical difference.

Re: Drone Footage of Arecibo Observatory Collapse

#99

Post by lotu »

blhack wrote: post #17

Is there any chance at all that this gets rebuilt? Is anybody even putting the costs requirements together to do it, or is this just a total loss? This is so unbelievably sad to see. It reminds me of seeing Notre Dame burning last year.

The only way I see that happening is if we can get congress to allocate funding for a new one. It would be seen as widely popular move so I don't think there is zero chance, but it would take a concerted publicity effort
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