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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 cod

by est31 6y ago

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 closer inspection, the first event is actually multiple smaller ones, not sure if they are related to the collapse at all. The second event is clearly one discrete thing though. The image was uploaded to twitter at 11:56 UTC, so minutes within the collapse being recorded on the seismograph. You can still see the dust in the air. Pretty cool that all this data is out there, in the open, just a curl request away. [0]: https://www.fdsn.org/networks/detail/PR/ https://www.fdsn.org/networks/detail/PR/ [1]: Note on some of the screenshots I've preprocessed the data with a lowpass filter st.filter("lowpass", freq=0.1, corners=2) to make it look nicer, while in others I haven't. I'm just an interested person, not doing this on a scientific level. https://imgur.com/a/FjrbWWa https://imgur.com/a/FjrbWWa

leephillips 6y ago
Interesting! You should write this up. Your comment has more content than most Medium articles that I’ve seen.
- est31 6y ago
  Thanks! I mainly just googled together this stuff in a matter of 1-2 hours. So it was an afternoon project :). But maybe I'll write it into a nice format. It wasn't trivial because the WWW interfaces only show earthquakes but this event was likely only registered by one station and had too low magnitude to be registered by others, and was thus filtered out.
prionassembly 6y ago
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.
- toomuchtodo 6y ago
  https://earthquake.usgs.gov/earthquakes/map/ https://earthquake.usgs.gov/earthquakes/map/ http://ds.iris.edu/ds/nodes/dmc/data/ http://ds.iris.edu/ds/nodes/dmc/data/
- IvyMike 6y ago
  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/ https://raspberryshake.org/data-center/
ssivark 6y ago
Official report from the NSF: https://www.nsf.gov/news/news_summ.jsp?cntn_id=301737 https://www.nsf.gov/news/news_summ.jsp?cntn_id=301737
- _Microft 6y ago
  Very cool, that matches it. According to Wolfram Alpha, 7:55 a.m. Atlantic Standard Time is 11:55 UTC.
  - est31 6y ago
    There is a small difference of 3 minutes, but the NSF wording has an "approximately". I guess their priority was to get an initial report out and not precisely determine when it collapsed. I think that a final report on the incident will contain the 12:52 figure instead of the 12:55 one. Anyways, that's just splitting hairs. Glad that nobody got hurt. This incident is obviously a tragedy.
dheera 6y ago
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 6y ago
  [deleted]
- scollet 6y ago
  Not stupid. Also wondering this. Maybe it would be cheaper to use more efficient materials and engineering as well as perform another geo survey.
- petschge 6y ago
  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.
  - dheera 6y ago
    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?
    - petschge 6y ago
      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.
piannucci 6y ago
Whoa, cool. Could you make a .wav file or something so we can hear it?
driverdan 6y ago
The 23:12 event could have been a cable failure which lead to the eventual collapse at 11:52.
NikolaeVarius 6y ago
According to this Scott Manley video there was an earthquake in the Dominican Republic that may have been responsible for the break. Timing matches up. Trying to find his source https://www.youtube.com/watch?v=vchDbyIRP44 https://www.youtube.com/watch?v=vchDbyIRP44
- est31 6y ago
  In the video he shows a screenshot from facebook while mentioning the earthquake. I dug it up, seems to be this post: https://www.facebook.com/redsismicadepuertorico/photos/a.10150181523721108/10159028057111108 https://www.facebook.com/redsismicadepuertorico/photos/a.101... > 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. That facebook post is waaaay better than what I as a layman was able to come up in the post above. We made both posts at the same time though, so I couldn't know any better. Also thanks for posting the link to the video, it's precisely the kind of breakdown I like :).
betwixthewires 6y ago
Do you happen to know of some sources where I can find more API access to data and information like this? I'd love to be able to pull seismic data, weather data, ambient light data (as examples) or any other kind of data from all over the world just for fun.
- est31 6y ago
  The seismic data I downloaded using the FDSN web API. The link is on the page I linked in the "Data Access" section: https://www.fdsn.org/networks/detail/PR/ https://www.fdsn.org/networks/detail/PR/ > FDSN Web Services provide a common data access API for seismic data. For weather data, I found this page by googling: https://www.weather.gov/documentation/services-web-api https://www.weather.gov/documentation/services-web-api Generally I think it's better to get it from commercial vendors, because a lot of weather stations/data are only available commercially.

by est31 6y ago

leephillips 6y ago

Interesting! You should write this up. Your comment has more content than most Medium articles that I’ve seen.

est31 6y ago
Thanks! I mainly just googled together this stuff in a matter of 1-2 hours. So it was an afternoon project :). But maybe I'll write it into a nice format. It wasn't trivial because the WWW interfaces only show earthquakes but this event was likely only registered by one station and had too low magnitude to be registered by others, and was thus filtered out.

prionassembly 6y ago

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.

toomuchtodo 6y ago
https://earthquake.usgs.gov/earthquakes/map/ https://earthquake.usgs.gov/earthquakes/map/ http://ds.iris.edu/ds/nodes/dmc/data/ http://ds.iris.edu/ds/nodes/dmc/data/
IvyMike 6y ago
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/ https://raspberryshake.org/data-center/

ssivark 6y ago

Official report from the NSF: https://www.nsf.gov/news/news_summ.jsp?cntn_id=301737 https://www.nsf.gov/news/news_summ.jsp?cntn_id=301737

_Microft 6y ago
Very cool, that matches it. According to Wolfram Alpha, 7:55 a.m. Atlantic Standard Time is 11:55 UTC.
- est31 6y ago
  There is a small difference of 3 minutes, but the NSF wording has an "approximately". I guess their priority was to get an initial report out and not precisely determine when it collapsed. I think that a final report on the incident will contain the 12:52 figure instead of the 12:55 one. Anyways, that's just splitting hairs. Glad that nobody got hurt. This incident is obviously a tragedy.

dheera 6y ago

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 6y ago
[deleted]
scollet 6y ago
Not stupid. Also wondering this. Maybe it would be cheaper to use more efficient materials and engineering as well as perform another geo survey.
petschge 6y ago
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.
- dheera 6y ago
  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?
  - petschge 6y ago
    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.

piannucci 6y ago

Whoa, cool. Could you make a .wav file or something so we can hear it?

driverdan 6y ago

The 23:12 event could have been a cable failure which lead to the eventual collapse at 11:52.

NikolaeVarius 6y ago

According to this Scott Manley video there was an earthquake in the Dominican Republic that may have been responsible for the break. Timing matches up. Trying to find his source https://www.youtube.com/watch?v=vchDbyIRP44 https://www.youtube.com/watch?v=vchDbyIRP44

est31 6y ago
In the video he shows a screenshot from facebook while mentioning the earthquake. I dug it up, seems to be this post: https://www.facebook.com/redsismicadepuertorico/photos/a.10150181523721108/10159028057111108 https://www.facebook.com/redsismicadepuertorico/photos/a.101... > 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. That facebook post is waaaay better than what I as a layman was able to come up in the post above. We made both posts at the same time though, so I couldn't know any better. Also thanks for posting the link to the video, it's precisely the kind of breakdown I like :).

betwixthewires 6y ago

Do you happen to know of some sources where I can find more API access to data and information like this? I'd love to be able to pull seismic data, weather data, ambient light data (as examples) or any other kind of data from all over the world just for fun.

est31 6y ago
The seismic data I downloaded using the FDSN web API. The link is on the page I linked in the "Data Access" section: https://www.fdsn.org/networks/detail/PR/ https://www.fdsn.org/networks/detail/PR/ > FDSN Web Services provide a common data access API for seismic data. For weather data, I found this page by googling: https://www.weather.gov/documentation/services-web-api https://www.weather.gov/documentation/services-web-api Generally I think it's better to get it from commercial vendors, because a lot of weather stations/data are only available commercially.