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Arecibo Observatory Collapsed

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Re: Arecibo Observatory Collapsed

#211

Post by AnimalMuppet »

hedora wrote: post #205
AnimalMuppet wrote: post #183

Earlier quoted context omitted.

OK, things are starting to make sense. It's an alien attack. They created Covid to distract us enough that we wouldn't defend Arecibo. And they're driving Trump insane with their mind control rays just to increase the chaos. /s, in case anyone couldn't tell...

Too soon on the mind control ray thing. The Russians are allegedly microwaving the brains of CIA agents and their families, and the intelligence community is waiting until Trump is gone to mount a response. Citation (and perhaps tin foil hat) obviously required: https://www.gq.com/story/cia-investigation-and-russian-micro...

They think that Biden is going to be more likely to allow a response? That seems... improbable.

Re: Arecibo Observatory Collapsed

#212

Post by colechristensen »

ryandrake wrote: post #128
colechristensen wrote: post #73

Earlier quoted context omitted.

One important piece of military preparedness is having a population of experienced engineers, manufacturing infrastructure, leadership, R&D, etc. Institutional knowledge is very real. Weapons programs also simply take decades. You might be able to churn out web apps in a few months, but cutting edge aircraft, not so much. What do we have? Unprecedented world peace. Why do we have it? American foreign policy. You have…

> What do we have? Unprecedented world peace. Why do we have it? American foreign policy. Wait, what? There have been hundreds of armed conflicts going on around the world since the end of WW2, many of which were either directly instigated by the USA or at least involved the USA. There are dozens going on right now [1] some resulting in massive casualties. I don't think we will ever see world peace. You don't mass-pr…

It isn’t about absolute peace, that is practically impossible.

It’s about relative peace, worldwide number of conflicts, casualty rate by population, geographical spread of conflicts, etc.

What is unprecedented is your chance of being killed in war has gone down substantially and stayed down after WWII. The types of conflicts have changed, civil wars now dominate, other types have gone down significantly or have been eliminated. There have not been conflicts between major military powers.

Re: Arecibo Observatory Collapsed

#213

Post by [deleted] »

dheera wrote: post #208
est31 wrote: post #88

I've wondered about the exact time of the collapse. Apparently there is a seismic observatory only tens of meters away from the telescope dish. The station code is AOPR [0]. After retrieving the mseed data from the web API using curl, and installing obspy from pip, I could plot the events. This is the result: [1]. You can see two "events". One at Nov 30, 23:12 UTC, and a second, larger one at Dec 1st, 11:52 UTC. Upon…

Stupid question: Why do they decommission it instead of fixing it? It seems that it would be more work to build a new one.

[deleted]

Re: Arecibo Observatory Collapsed

#214

Post by schoen »

nickff wrote: post #207
AlexandrB wrote: post #196

Earlier quoted context omitted.

The F-35 is an example of the broken window parable[1] writ large. Sure it created a bunch of jobs, but that same money could have created a similar number of jobs while accomplishing something useful. I often wonder what the eventual consequences of this kind of resource misallocation will be for the US. [1] https://en.wikipedia.org/wiki/Parable_of_the_broken_window

Well, many influential economists don't believe in the broken windows fallacy, or that it applies here. Joseph Stiglitz has said that he was in favor of literally paying people to dig holes then fill them back up as a form of fiscal stimulus.

The original statement of this idea is from John Maynard Keynes in his General Theory, and turns out to run

> If the Treasury were to fill old bottles with banknotes, bury them at suitable depths in disused coal mines which are then filled up to the surface with town rubbish, and leave it to private enterprise on well tried principles of Laissez Faire to dig the notes up again (the right to do so being obtained, of course, by tendering for leases of the note-bearing territory), there need be no more unemployment and, with the help of the repercussions, the real income of the community, and its capital wealth also, would probably become a good deal greater than it actually is. It would, indeed, be more sensible to build houses and the like; but if there are political and practical difficulties in the way of this, the above would be better than nothing.

Re: Arecibo Observatory Collapsed

#215

Post by scollet »

dheera wrote: post #208
est31 wrote: post #88

I've wondered about the exact time of the collapse. Apparently there is a seismic observatory only tens of meters away from the telescope dish. The station code is AOPR [0]. After retrieving the mseed data from the web API using curl, and installing obspy from pip, I could plot the events. This is the result: [1]. You can see two "events". One at Nov 30, 23:12 UTC, and a second, larger one at Dec 1st, 11:52 UTC. Upon…

Stupid question: Why do they decommission it instead of fixing it? It seems that it would be more work to build a new one.

Not stupid. Also wondering this. Maybe it would be cheaper to use more efficient materials and engineering as well as perform another geo survey.

Re: Arecibo Observatory Collapsed

#216

Post by petschge »

dheera wrote: post #208
est31 wrote: post #88

I've wondered about the exact time of the collapse. Apparently there is a seismic observatory only tens of meters away from the telescope dish. The station code is AOPR [0]. After retrieving the mseed data from the web API using curl, and installing obspy from pip, I could plot the events. This is the result: [1]. You can see two "events". One at Nov 30, 23:12 UTC, and a second, larger one at Dec 1st, 11:52 UTC. Upon…

Stupid question: Why do they decommission it instead of fixing it? It seems that it would be more work to build a new one.

Reason 1: because they were afraid of it failing catastrophically just like what happened this morning. One person was on site (director of telescope operations Angel), but imagine what would have happened if a work crew was up in the structure working on cables during such a failure.

Reason 2: They are not going to build a new one. NSF has tried to get rid of AO for a long time now.

Re: Arecibo Observatory Collapsed

#217

Post by bigbubba »

olsonjeffery wrote: post #76
dmurray wrote: post #41

Earlier quoted context omitted.

Well, there was a bit of incompetence. The auxiliary cable was almost certainly installed incorrectly and the failure mode that occurred (cable slipped out of its socket) would not have happened if best practices were followed. But it was installed on the cheap: if they'd had more money they would likely have paid for more diligent engineers. After all, they built it pretty well the first time round. So at some level…

>Well, there was a bit of incompetence. Where? What evidence do you have for such a claim? >The auxiliary cable was almost certainly installed incorrectly Are you almost certain? How do you know? What stopped you from being completely certain? >and the failure mode that occurred (cable slipped out of its socket) would not have happened if best practices were followed. Are you a radio observatory specialist? Please sh…

When it comes to the matter of cables failing, you should look to a specialist in cables, not radio telescopes.

Re: Arecibo Observatory Collapsed

#218

Post by dheera »

petschge wrote: post #216
dheera wrote: post #208

Earlier quoted context omitted.

Stupid question: Why do they decommission it instead of fixing it? It seems that it would be more work to build a new one.

Reason 1: because they were afraid of it failing catastrophically just like what happened this morning. One person was on site (director of telescope operations Angel), but imagine what would have happened if a work crew was up in the structure working on cables during such a failure. Reason 2: They are not going to build a new one. NSF has tried to get rid of AO for a long time now.

Re: Reason 1

Well sure, but a hypothetical new structure is also going to require cables, just hopefully a more reliable construction. So why not keep the dish for now, and consider rebuilding the cables in a more modern fashion, and with redundant cables?

Re: Arecibo Observatory Collapsed

#219

Post by IvyMike »

prionassembly wrote: post #160
est31 wrote: post #88

I've wondered about the exact time of the collapse. Apparently there is a seismic observatory only tens of meters away from the telescope dish. The station code is AOPR [0]. After retrieving the mseed data from the web API using curl, and installing obspy from pip, I could plot the events. This is the result: [1]. You can see two "events". One at Nov 30, 23:12 UTC, and a second, larger one at Dec 1st, 11:52 UTC. Upon…

Any hints on finding seismic data from elsewhere in the world? There was a small event in South America yesterday I'd love to hit with data sciency stuff.

Raspberry Shake (citizen science seismometer network) may be interesting to you. I haven't used it myself, so I'm not sure if it's real time: https://raspberryshake.org/data-center/

Re: Arecibo Observatory Collapsed

#220

Post by petschge »

dheera wrote: post #218
petschge wrote: post #216

Earlier quoted context omitted.

Reason 1: because they were afraid of it failing catastrophically just like what happened this morning. One person was on site (director of telescope operations Angel), but imagine what would have happened if a work crew was up in the structure working on cables during such a failure. Reason 2: They are not going to build a new one. NSF has tried to get rid of AO for a long time now.

Re: Reason 1 Well sure, but a hypothetical new structure is also going to require cables, just hopefully a more reliable construction. So why not keep the dish for now, and consider rebuilding the cables in a more modern fashion, and with redundant cables?

The cables were (originally) redundant. There are actually replacement cables on the way from Germany right now. But after the one main cable failed earlier this year they noticed that all cables are MUCH weaker than previously thought. So there was (even before the collapse) no way of replacing the existing cables with the replacements. And yes that probably implies that they should have swapped out all cables years ago. But they didn't have the funding.
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