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The main purpose was militaristic and science benefited as a result. Like others have said, the technology has advanced to the point where it didn’t have much s

The main purpose was militaristic and science benefited as a result. Like others have said, the technology has advanced to the point where it didn’t have much scientific value and we no longer need it to spy on the Russians so I highly doubt anyone is willing to pony up the billions just to have something cool and inspirational when it won’t even be cutting edge anymore

jjk166 4y ago
Arecibo was never intended to spy on the Russians, nor is it capable of doing so - it's facing completely the wrong way. Arecibo did receive military funding, but that was because the military was interested in the behavior of the ionosphere. It was always a general science and technology development platform.
- nomel 4y ago
  https://news.ycombinator.com/item?id=33234109 https://news.ycombinator.com/item?id=33234109 Soviet tech allowed members, and equipment, to cross the borders of the country. ;)
  - jjk166 4y ago
    Again, this doesn't stand up to scrutiny. To pick up radar transmissions reflected off the moon, the moon has to be in line of sight for both the emitter and detector. Puerto Rico is just about the worst positioned place in the US for something to have the moon in line of sight at the same time as the soviet union, and the particular design of Arecibo further limits the angles it can be directed at, so it can't even look towards the horizon where it might conceivably stand a chance. It's fine for a telescope as the rotation of the Earth allows it to look at different parts of the sky at different times, but there's a reason no radio receivers for terrestrial communication are built that way. Further, Arecibo works at frequencies of 10-40 MHz, substantially lower than even the lowest frequency radars. With secondary reflections you might be able to detect that a radar pulse had been detected, but determining where it came from or even what emitted it would be extremely challenging. I suppose perhaps Cuba could have been spied upon with it, but again it's just the worst design for the application.
    - nomel 4y ago
      If you have any insight into the (dis)credibility of Steve Blank's talk, I would suggest opening a discussion on the talk page, so it can be removed.
hengheng 4y ago
Err, how was Arecibo able to spy on the Russians? Were there satellites going right over the dish?
- dwringer 4y ago
  On Wikipedia is the claim "The telescope also originally had military intelligence uses, including locating Soviet radar installations by detecting their signals bouncing off the Moon."[0], which gives this[1](by name, but unlinked) as its source. It would be interesting to know more. [0] https://en.wikipedia.org/wiki/Arecibo_Telescope https://en.wikipedia.org/wiki/Arecibo_Telescope [1] https://www.youtube.com/watch?v=ZTC_RxWN_xo https://www.youtube.com/watch?v=ZTC_RxWN_xo
  - Andrew_nenakhov 4y ago
    These sneaky scientists are always ready to fool silly military people into funding their extravagant scientific projects by promising it to have military uses.
nullc 4y ago
> where it didn’t have much scientific value EEEeeee.. don't confuse the weird biases in scientific research from publication incentives as being a true metric of scientific utility. There is a tremendous bias in favor of "new" instruments because the low hanging discoveries made possible on something new (not even necessarily 'better' just different) haven't been made yet. But much of that research is extremely superficial and doesn't go on to contribute much to the forward body of knowledge -- it just helps churn out papers to support career progression. Arecibo was thoroughly unmatched in several respects, particular as a radar[1]. It was also the premier instrument for validating observations made on synthetic aperture instruments since as a single aperture it's largely free of the artifacts that synthetic aperture instruments. Validation is scientifically critical but also doesn't tend to produce a lot of high profile papers. [1] E.g. consider these images of the moon imaged using Arecibo as the transmitter and Green Bank Telescope as the receiver https://sservi.nasa.gov/wp-content/uploads/2014/05/craters2labeled_nrao.jpg https://sservi.nasa.gov/wp-content/uploads/2014/05/craters2l...

jjk166 4y ago

Arecibo was never intended to spy on the Russians, nor is it capable of doing so - it's facing completely the wrong way. Arecibo did receive military funding, but that was because the military was interested in the behavior of the ionosphere. It was always a general science and technology development platform.

nomel 4y ago
https://news.ycombinator.com/item?id=33234109 https://news.ycombinator.com/item?id=33234109 Soviet tech allowed members, and equipment, to cross the borders of the country. ;)
- jjk166 4y ago
  Again, this doesn't stand up to scrutiny. To pick up radar transmissions reflected off the moon, the moon has to be in line of sight for both the emitter and detector. Puerto Rico is just about the worst positioned place in the US for something to have the moon in line of sight at the same time as the soviet union, and the particular design of Arecibo further limits the angles it can be directed at, so it can't even look towards the horizon where it might conceivably stand a chance. It's fine for a telescope as the rotation of the Earth allows it to look at different parts of the sky at different times, but there's a reason no radio receivers for terrestrial communication are built that way. Further, Arecibo works at frequencies of 10-40 MHz, substantially lower than even the lowest frequency radars. With secondary reflections you might be able to detect that a radar pulse had been detected, but determining where it came from or even what emitted it would be extremely challenging. I suppose perhaps Cuba could have been spied upon with it, but again it's just the worst design for the application.
  - nomel 4y ago
    If you have any insight into the (dis)credibility of Steve Blank's talk, I would suggest opening a discussion on the talk page, so it can be removed.

hengheng 4y ago

Err, how was Arecibo able to spy on the Russians? Were there satellites going right over the dish?

dwringer 4y ago
On Wikipedia is the claim "The telescope also originally had military intelligence uses, including locating Soviet radar installations by detecting their signals bouncing off the Moon."[0], which gives this[1](by name, but unlinked) as its source. It would be interesting to know more. [0] https://en.wikipedia.org/wiki/Arecibo_Telescope https://en.wikipedia.org/wiki/Arecibo_Telescope [1] https://www.youtube.com/watch?v=ZTC_RxWN_xo https://www.youtube.com/watch?v=ZTC_RxWN_xo
- Andrew_nenakhov 4y ago
  These sneaky scientists are always ready to fool silly military people into funding their extravagant scientific projects by promising it to have military uses.

nullc 4y ago

> where it didn’t have much scientific value EEEeeee.. don't confuse the weird biases in scientific research from publication incentives as being a true metric of scientific utility. There is a tremendous bias in favor of "new" instruments because the low hanging discoveries made possible on something new (not even necessarily 'better' just different) haven't been made yet. But much of that research is extremely superficial and doesn't go on to contribute much to the forward body of knowledge -- it just helps churn out papers to support career progression. Arecibo was thoroughly unmatched in several respects, particular as a radar[1]. It was also the premier instrument for validating observations made on synthetic aperture instruments since as a single aperture it's largely free of the artifacts that synthetic aperture instruments. Validation is scientifically critical but also doesn't tend to produce a lot of high profile papers. [1] E.g. consider these images of the moon imaged using Arecibo as the transmitter and Green Bank Telescope as the receiver https://sservi.nasa.gov/wp-content/uploads/2014/05/craters2labeled_nrao.jpg https://sservi.nasa.gov/wp-content/uploads/2014/05/craters2l...