Iconic Arecibo Observatory crumples after cable and structural failures

Cal Jeffrey

Posts: 2,728   +662
Staff member
What just happened? The Arecibo Radio Observatory located in Puerto Rico has collapsed sometime between late Monday evening and early Tuesday morning. The radio telescope has suffered multiple cable failures in the preceding months, and officials had cordoned it off for safety issues. Nobody was hurt in the collapse.

Last month, the National Science Foundation decided there was no safe way to repair Arecibo's support cables, which failed in August and again in November. The NSF determined it would be safer to take down the facility in a controlled demolition. However, before it could even schedule the decommission, the structure ultimately failed, sending the 900-ton platform suspended above the telescope's 1,000-foot dish crashing down.

"We are saddened by this situation but thankful that no one was hurt," said NSF Director Sethuraman Panchanathan in a statement. "Our focus is now on assessing the damage, finding ways to restore operations at other parts of the observatory, and working to continue supporting the scientific community and the people of Puerto Rico."

The NSF's initial assessment is that the tops of the support towers suspending the platform gave way. Indeed, before-and-after pictures (see above tweets) from meteorologist Deborah Martorell show the tops of the surrounding structures appear to have broken off. Another image shows the radio dish utterly destroyed. The NSF is still assessing how to clear the site safely.

The Arecibo Radio Observatory was a research facility designed for various astronomy tasks, including tracking asteroids, but is more famous for its SETI (Search for Extra-Terrestrial Intelligence) work. Its iconic features were made famous in the 90s by the observatory's several appearances in pop-culture media, including the GoldenEye film (1995) and video game (1997), the movies Species (1995) and Contact (1997), and an episode of the television series The X-Files (1994).

Image credit: Mia2you

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QuantumPhysics

Posts: 4,064   +4,162
If the government stopped funding it, that means they don't care about it and it isn't necessary anymore.

NOW, on a side note: in the movie "The Arrival" we see the main character using a laptop to hack neighborhood satellite dishes to use them as a radio telescope.

Is that possible?

Why does Direct TV leave dishes on our houses instead of taking the equipment back???
 

BrotherMichigan

Posts: 10   +18
If the government stopped funding it, that means they don't care about it and it isn't necessary anymore.
Speaking as an actual astrophysicist, that is far from reality. The government doesn't really care about ANY of the instruments or sites and it is a constant fight to get the funding to keep them all running. For the scientists, Arecibo was a unique facility that was being used to conduct important observations that will basically be impossible now that it is gone.
 

Endymio

Posts: 1,340   +1,214
In the movie "The Arrival" we see the main character using a laptop to hack neighborhood satellite dishes to use them as a radio telescope. Is that possible?
Except for the fact that they're all pointed at the same point in the sky and cannot be repositioned, the receiver circuitry is hard-wired to a specific frequency set, and even if a hacker could access your satellite box, the hardware doesn't allow access to the raw antenna signal anyway.

Other than that, yes, it's as plausible as anything else you see in a fictional Hollywood film.
 

Uncle Al

Posts: 7,770   +6,401
If the government stopped funding it, that means they don't care about it and it isn't necessary anymore.

NOW, on a side note: in the movie "The Arrival" we see the main character using a laptop to hack neighborhood satellite dishes to use them as a radio telescope.

Is that possible?

Why does Direct TV leave dishes on our houses instead of taking the equipment back???
I believe, from other reports I read, the problem wasn't a matter of lack of funding but of the numerous hurricanes and earthquakes it had endured in just the past 12 months .... they simply could not keep up on the maintenance fast enough to save it. A real shame. I got to fly over it once and even from 5,000 feet it still looked massive and nothing less than impressive.
 

wiyosaya

Posts: 5,569   +3,753
Speaking as an actual astrophysicist, that is far from reality. The government doesn't really care about ANY of the instruments or sites and it is a constant fight to get the funding to keep them all running. For the scientists, Arecibo was a unique facility that was being used to conduct important observations that will basically be impossible now that it is gone.
I have a relative who works at a university lab that is also a major US energy laboratory. When 45 came in, their funding was threatened. Battling for funds each year must be a challenge. I would imagine that labs have people who are hired specifically to do battle for funds from the government.
 
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mbrowne5061

Posts: 1,725   +979
I believe, from other reports I read, the problem wasn't a matter of lack of funding but of the numerous hurricanes and earthquakes it had endured in just the past 12 months .... they simply could not keep up on the maintenance fast enough to save it. A real shame. I got to fly over it once and even from 5,000 feet it still looked massive and nothing less than impressive.
That certainly hastened its demise, but the cables failed at only 60% of their rated strength. Hurricanes and earthquakes wouldn't do that alone. Only decades of corrosion, without the proper maintenance schedule would do that.

If the government stopped funding it, that means they don't care about it and it isn't necessary anymore.
That dish was our only near-earth asteroid monitoring radar. So, yeah, totally unnecessary.

NOW, on a side note: in the movie "The Arrival" we see the main character using a laptop to hack neighborhood satellite dishes to use them as a radio telescope.

Is that possible?
Not even a little.

The dishes on the side of your house do not have the power to transmit at the necessary levels, they do not have the sensitivity to receive at the power signals come in at, nor would their dish size even be physically able to collect the incoming radio waves and focus them onto its aperture.

Radio astronomy dishes are the sizes they are for a reason. Yes, you can network dishes together - like at the NRAO Very Large Array - to synthesize a larger dish, but that involves a lot of specialized hardware that was designed to facilitate this. But even then, building a single dish of 'equivalent' size would yield superior results when compared to the network one.
 
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wiyosaya

Posts: 5,569   +3,753
That certainly hastened its demise, but the cables failed at only 60% of their rated strength. Hurricanes and earthquakes wouldn't do that alone. Only decades of corrosion, without the proper maintenance schedule would do that.

That dish was our only near-earth asteroid monitoring radar. So, yeah, totally unnecessary.
However, not the only effort to detect and monitor NEOs. Anyone with a computer that would like to contribute to the effort should have a look at https://asteroidsathome.net/boinc/

Yes, you can network dishes together - like at the NRAO Very Large Array - to synthesize a larger dish, but that involves a lot of specialized hardware that was designed to facilitate this. But even then, building a single dish of 'equivalent' size would yield superior results when compared to the network one.
Just like any astronomical interferemeter including optical ones.
 
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mbrowne5061

Posts: 1,725   +979
However, not the only effort to detect and monitor NEOs. Anyone with a computer that would like to contribute to the effort should have a look at https://asteroidsathome.net/boinc/
Astronomical radar isn't used to detect or monitor NEOs. Radar's field of view is either just too narrow to monitor the whole sky, or so wide that it is effectively useless at the distances and target sizes in question. Optical tracking and detection is better here.

Radar is used to figure out their composition and refine orbital data after and asteroid has been discovered. Optical observation, or observation in other portions in different parts of the EM spectrum, cannot produce the kind of information to determine with an asteroid is a hunk of solid metal that could plow right through the atmosphere, or a rubble pile that would just be a pretty light show as it broke up. Optical observation is also a lot less accurate when plotting motion (orbital and rotation)

With the loss of Arecibo, it doesn't really matter if you identify a new asteroid on a potential collision course with earth. You cannot produce the data to refine its projected trajectory to be certain of an impact or miss, nor can you produce the data to determine if an asteroid is a threat in the event of contact with our atmosphere. Knowing our politicians, this would mean just ignoring any potential threat until it is too late to do something because 'this data could be anything, and I do not want to start a panic/pay for it'
 
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Endymio

Posts: 1,340   +1,214
The dishes [do] not have the sensitivity to receive at the power signals come in at, nor would their dish size even be physically able to collect the incoming radio waves and focus them onto its aperture.
Quite a bit of radio astronomy is done in the millimeter and submillimeter spectrum, which these dishes are more than large enough to capture.
 
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mbrowne5061

Posts: 1,725   +979
Quite a bit of radio astronomy is done in the millimeter and submillimeter spectrum, which these dishes are more than large enough to capture.
Large enough, yes. But curvature matters, and I would bet that the radius of the dish is not conducive to focusing the frequencies radio astronomers are monitoring onto the receiver.

Even if they are, it still doesn't solve the power and amplification shortfalls. No amount of clever signal processing can save you if you can't even begin to detect the signal in question.
 

Endymio

Posts: 1,340   +1,214
Large enough, yes. But curvature matters, and I would bet that the radius of the dish is not conducive to focusing the frequencies radio astronomers are monitoring
The DirectTV A-Band is in the 2ghz range: part of a microwave band commonly studied in radio astronomy. I'm not sure what you mean by "curvature", as all such dishes have a parabolic curve and focus all incident radiation identically.
 

mbrowne5061

Posts: 1,725   +979
The DirectTV A-Band is in the 2ghz range: part of a microwave band commonly studied in radio astronomy. I'm not sure what you mean by "curvature", as all such dishes have a parabolic curve and focus all incident radiation identically.
Think of it like chromatic aberration. Different frequencies reflect off and deflect through materials slightly differently, causing slight scattering and divergence (and maybe even a phase shift, depending on exact conditions), whether the photon is part of the radio spectrum or visual spectrum. Your satellite TV dish may be accurate and sensitive enough to pick up and resolve the signals from their satellites in orbit, but they almost certainly incapable of performing cutting edge radio astronomy research in those same frequencies.
 

Endymio

Posts: 1,340   +1,214
Think of it like chromatic aberration. Different frequencies reflect off and deflect through materials slightly differently...
No. They refract differently (see Snell's Law for details), but reflection angles depend only on the angle of incidence, not the frequency of the radiation. This is why all such radio dishes (and visible-spectrum ones as well) have the exact same parabolic curve.

Your satellite TV dish [is] almost certainly incapable of performing cutting edge radio astronomy research in those same frequencies.
Sorry, but this is incorrect also. Many people (including a former colleague of mine) have in fact used DirectTV dishes for amateur radio astronomy. The angular resolution is of course very low, but it's certainly workable ... and, in theory, capable of VLBI. I don't know anyone doing "cutting edge research" with them, of course, but then your original statement was that these dishes were physical incapable of collecting such signals.