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The thing was iconic... even if not everyone watching/playing Goldeneye knew it was a real radio telescope, it was nevertheless one of those science megaproject

• beambot 6y ago
  What comes next: Hopefully lunar-based optical & radio telescopes!
• ardy42 6y ago
  > But infrastructure ages, and 60 years isn't a bad run. What comes next? Clearly there's going to be a capabilities gap for a while, but now that it's 60 years after its original design, what kind of design is going to replace it? Do we even need giant monolith dishes anymore? China already built one: https://phys.org/news/2016-07-china-world-largest-radio-telescope.html https://phys.org/news/2016-07-china-world-largest-radio-tele.... Given that it's nonmilitary US government infrastructure, I doubt it will be replaced. After all, why spend money on a telescope when the government can cut the budget to lower taxes a little bit more?
  • adamc 6y ago
    Makes me sad.
  • Tuna-Fish 6y ago
    It wasn't nonmilitary, it's military use has just come to an end. In a small sidenote of an absolutely magnificent lecture by Steve Blank, the Secret History of Silicon Valley [0], he notes that the reason the radio telescopes were built in the 60's was because the Soviets were using air defense radars in their interiors that were hard to get information on using other methods that were available, but a few times a month a very sensitive radio telescope would get a very good view of their emissions as they bounced off the moon. This was the cause of the massive radio astronomy boom during the 60's that built all the western radio telescope megaprojects that have produced so much great scientific data. [0]: https://www.youtube.com/watch?v=ZTC_RxWN_xo https://www.youtube.com/watch?v=ZTC_RxWN_xo (radio telescope talk at 50m30s or so)
    • bullfightonmars 6y ago
      Well that is fascinating. I am reading The Sparrow by Mary Doria Russell. Part of the plot is that a radio astronomer at Arecibo discovers intermittent Alien radio signals originating from the Alpha Centari System. The protagonists can't figure out why the Alpha Centari's are transmitting such strong radio signals and why they are intermittent. It turns out that their planet doesn't have an ionosphere to reflect broadcast radio waves, so the inhabitants instead bounce radio off the moon to broadcast it back to the surface. Arecibo only picked up the radio signals when they bounced off the moon at the right angle. The origin of radio telescopes in the 60s must be the kernel for that bit of plot.
      • lightlyused 6y ago
        The Sparrow is an excellent but distributing book.
        • twic 6y ago
          Personally i couldn't stand it, because it felt like telling a straightforward story out of order was a trick to make that story seem more interesting than it really was. But i encourage everyone to read it and form their own opinion!
    • 6y ago
  • xyzzyz 6y ago
    > After all, why spend money on a telescope when the government can cut the budget to lower taxes a little bit more? The NSF budget had been steadily growing in real terms, and is now over 3 times larger than in early 80s (8 times in nominal terms). If Arecibo has not been getting enough money to maintain it, and if there is no plan for new telescope in its budget, it’s not because of “budget cuts”, but rather because of spending decisions. I do believe that we are getting less than we used to for the spend, but it’s clear that it’s not budget cuts that are responsible: rather, it’s the productivity of science is falling, and so is efficiency of the government, despite growing expenditures.
    • 1MoreThing 6y ago
      Is it productivity, or is the work to mine new "knowledge coins" just harder now that we've done some of the easier work?
      • chordalkeyboard 6y ago
        That is an excellent question that also strikes to the heart of how we measure "productivity."
      • xyzzyz 6y ago
        By falling productivity, I simply mean that the same amount of funding results in fewer, less valuable and less useful results. Whether it’s caused by research itself becoming progressively more difficult, or some kind of fundamental dysfunction within science, I cannot accurately determine: I think it’s both at least to some degree. I think it’s reasonable to expect that keeping pace of results requires growth in spending, in general.
  • javert 6y ago
    The government does not cut the budget. It is ever-growing. Republicans lower taxes sometimes. They re-allocate budget from one thing to another. They don't cut the budget.
    • Florin_Andrei 6y ago
      It's almost as if this is correlated with the population increase. Almost.
      • javert 6y ago
        Except growth of the budget outstrips growth of the population, enormously. Please cut out the sarcasm. Let's be nice to one another. (And if you didn't mean it to be sarcasm, never mind.)
  • Aeolun 6y ago
    It seems like we should be able to build these things in space.
    • bronson 6y ago
      We can. They would be vastly more expensive than the telescopes we're building on earth, and uneconomical to fix or upgrade. One day we'll have synthetic aperture radiotelescope swarms in space. For now, it's a better use of money to improve our earth-based systems first.
• libraryofbabel 6y ago
  Not a radio astronomer (hoping one chimes in), but my understanding is that it’s about sensitivity (what’s the faintest signal it can detect) and resolution (distinguishing signals from points close together in the sky). The Very Large Array has “the resolution of an antenna 36 km (22 miles) across, with the equivalent sensitivity of a dish 130 meters (422 feet) in diameter”[0], i.e. amazing resolution but sensitivity much smaller than the current largest single dish, which is China’s FAST (500 meters in diameter). [0] http://www.vla.nrao.edu/ http://www.vla.nrao.edu/
• aylmao 6y ago
  > But infrastructure ages, and 60 years isn't a bad run. Infrastructure can also be maintained and last longer than this, which is why I'm personally sad. Had Arecibo always had the ~60 year timeline, it would've been a bittersweet retirement, like Voyager. In this case I just feel like it's gone before it should. Arecibo has been receiving reduced funding since the early 2000s [1]. The end of an era, although thankfully not of science mega-projects. There's still plenty of cool ones operating or under construction. [1]: https://en.wikipedia.org/wiki/Arecibo_Observatory#Funding_concerns https://en.wikipedia.org/wiki/Arecibo_Observatory#Funding_co...
  • Retric 6y ago
    It really depends on the structure. Giant steel objects are much harder to keep intact, to the point where non iconic objects are easier to replace once than maintain for 100+ years.
    • goatinaboat 6y ago
      Giant steel objects are much harder to keep intact, to the point where non iconic objects are easier to replace once than maintain for 100+ years. What about the Eiffel Tower? Or Blackpool Tower. That proves it can be done.
      • oillio 6y ago
        Those are iconic. The difference between being possible and being cost effective.
      • Miraste 6y ago
        Those are both made of iron.
        • spiritplumber 6y ago
          So they're iconic and ironic.
• antognini 6y ago
  It's been a little while since I dabbled in radio astronomy, but arrays like the VLA use interferometry to produce high resolution images. However, the high resolution is only along the directions between pairs of telescopes. Since you don't have telescopes in all directions, there are some directions with low resolution and others with high resolution. (In the technical parlance they talk about "UV-coverage" and filling the UV plane".) This produces patterns in the Fourier domain that look like this: http://www.aoc.nrao.edu/~vlbacald/idx/snap_uv.gif http://www.aoc.nrao.edu/~vlbacald/idx/snap_uv.gif. [1] As the object moves in the sky, these dots move around and sort of "fill out" the image in Fourier space, so you get coverage that could look like this: http://www.aoc.nrao.edu/~vlbacald/idx/lowd_uv.gif http://www.aoc.nrao.edu/~vlbacald/idx/lowd_uv.gif but it's still not 100% full. The advantage of a telescope that is a single large dish like Arecibo is that this plane is completely filled. The resolution is more or less the same in all directions. The main disadvantage, of course, is that it is embedded in the ground and can only look at what is directly overhead. (They can maneuver the secondary dish to look at things a little bit away from directly overhead, but I seem to remember it only being a few degrees.) [1]: See this page for those images and more details: http://www.aoc.nrao.edu/~vlbacald/read.shtml http://www.aoc.nrao.edu/~vlbacald/read.shtml
  • mumblemumble 6y ago
    Could this characteristic be mitigated by arranging the telescopes in a random pattern rather than using simple, regular pattern like the VLA follows? That seems like it might be what's going on with the UV coverage diagrams being demonstrated at the bottom of page 3 in this paper about the ATA: https://www.seti.org/sites/default/files/ATA-memo-series/memo15.pdf https://www.seti.org/sites/default/files/ATA-memo-series/mem...
    • petschge 6y ago
      You can improve UV coverage a bit but removing redundant duplicate baselines. Which is what pseudo-random patterns do. And these are used e.g. by Lofar. But the problem of lacking very small baselines to fill in very large scales on the sky remains. Interferometer are simply not very good for imaging extended objects. And of course the other thing is that you might have less reflective area in total and thus lower sensitivity for dim things.
• moonbug 6y ago
  > What comes next? The Square Kilometre Array
  • petschge 6y ago
    That the US (as of April 2020) does not take any part in.
    • moonbug 6y ago
      So what.
      • spenczar5 6y ago
        So many US astronomers will have trouble getting funding to use it, so it doesn’t replace Arecibo for that group, and a very large number of radio astronomers work at US institutions.
        • moonbug 6y ago
          So what
• SiempreViernes 6y ago
  Arecibo has been superseded in terms of raw aperture by FAST, and in terms of angular resolution by the interferometry arrays since 1966 at the latest when the One Mile observatory was doing 23 arcsecond resolution images. I think it's main somewhat unique capability was doing radar measurements of things in our solar system. My impressions is the neglect comes from having done all the useful things it could do ages ago, and not finding anything new to help with in the areas of science that gets funding. The state of the art interferometry arrays are ASKAP and MeerKAT currently, in the sense of being the newest and being precusors of the SKA which is the biggest project right now. In terms of best in class, it varies with the specific frequency and which bit of the sky you want to look at and also with what you consider an observatory: the Event Horizon Telescope that resolved the M87 black hole has the worlds best resolution at their mm wavelengths, but it's really a bunch of existing telescopes collaborating and not a purpose built facility.
  • Gibbon1 6y ago
    Am I wrong but I remember something that it's resolution sucks because it's not parabolic.
    • lightlyused 6y ago
      May be true, but its real value was has a radar.
      • bronson 6y ago
        The transmission capability is part of the reason Arecibo would be so difficult to fix. The platform is almost 900 tons. China's FAST telescope was designed without transmit, mostly to save on suspended weight. Its focus cabin is only 30 tons.
  • jasonwatkinspdx 6y ago
    Interferometry can simulate the resolution of a dish corresponding to its baseline but not the sensitivity. The VLA may simulate the resolution of a 36 km dish, but it has the sensitivity of a 130 meter one, considerably less than Arecibo's 305. You're ultimately limited by signal vs noise and can't make up for the receiving area that simply isn't there, no matter the width of the baseline. This makes interferometers and stationary giant dishes different tools, suited to different types of observations. Arrays are not good at imaging extended diffuse sources.
• fuoqi 6y ago
  >what kind of design is going to replace it? FAST [0] can be considered an Arecibo replacement, see the comparison chapter on the wiki page. Though it is built in China, so some may say that it's not a replacement for the US and the West science community. [0]: https://en.wikipedia.org/wiki/Five-hundred-meter_Aperture_Spherical_Telescope https://en.wikipedia.org/wiki/Five-hundred-meter_Aperture_Sp...
  • JshWright 6y ago
    FAST doesn't have some of the more interesting capabilities of Arecibo (most notably, the ability to perform radar astronomy).
• dheera 6y ago
  Random stupid questions from someone who is not a civil engineer: (a) Why not replace the cables? (b) What would they do if the cables on the Golden Gate bridge also corroded like this?
  • chordalkeyboard 6y ago
    judging by other comments, the observatory is obsolete. I believe they regularly paint the cables on the GG bridge in order to protect from corrosion.
  • dreamcompiler 6y ago
    The article suggests that the act of replacing the cables could cause a catastrophic failure. My interpretation of this is that unless one could replace all the cables at exactly the same time (which is impossible), at least one more would fail, which would almost certainly cause the instrument pod to fall, destroying the dish and damaging buildings with flying cables.
• bitexploder 6y ago
  SETI at home was always fun back in the day. I always thought it was cool to see data from that telescope.
• leoc 6y ago
  On this website we can't fail to mention the connection to James Burke's Connections: Arecibo Observatory appears in Episode 3 from 43:50 https://youtu.be/eCp8h9RkaSw?list=PLf02uWXhaGRng_YzH-Ser_VEV4lGSLX_1&t=2630 https://youtu.be/eCp8h9RkaSw?list=PLf02uWXhaGRng_YzH-Ser_VEV... (skip to 47:00 https://youtu.be/eCp8h9RkaSw?list=PLf02uWXhaGRng_YzH-Ser_VEV4lGSLX_1&t=2820 https://youtu.be/eCp8h9RkaSw?list=PLf02uWXhaGRng_YzH-Ser_VEV... for discussion of the obsevatory), including in some nice aerial shots.
• retostamm 6y ago
  Not a radioastronomer, but it seems like it'd be nice to add a dish the back of (some of the) Starlink satellites. To make an even larger array.
• kawfey 6y ago
  I used to work at the VLA as an RF engineering intern. I learned a lot. There is a good technical answer in these comments already, in regards to reception. But AO was also a transmitter - it could pump out millions of watts to illuminate asteroids, the moon, and other orbiting objects for mono static and bistatic radar measurements. For example, images such as these [0] are created by receiving the reflection of energy emitted from transmitters like AO and Goldstone (I didn’t find an exact image of an AO-VLA measurement but they’re out there). The AO and VLA had a unique relationship, in that one could precisely measure and image irregularities of any particular VLA dish panel down to a few tenths of a millimeter using bistatic radar of the moon. It’s somewhere in the eVLA library but my google fu is failing me (also google really sucks now). They also had a few events for ham radio where AO lit up the moon and hams across the world could hear its reflection with basic equipment. [1] [0] https://m-cacm.acm.org/careers/182810-high-def-radar-images-released-of-near-earth-asteroid/fulltext https://m-cacm.acm.org/careers/182810-high-def-radar-images-... [1] https://youtu.be/SUr1z5XeOE0 https://youtu.be/SUr1z5XeOE0
• ashtonkem 6y ago
  60 years in a tropical environment, no less. The humidity there cannot be kind to steel.
• samstave 6y ago
  Bezos should build an updated one there for his legacy!
• asgekar 6y ago
  Hi, A radio astronomer here, and writing opinion for all that's worth. I visited Arecibo once and stayed for a short project for 3 months. It was awesome, and they have a fabulous small astronomy team doing some really interesting science. My mentor and long-term collaborator has used this telescope since the 70s, and she will be devastated. This dish has produced so many unexpected discoveries, solid science of highest calibre, and has stayed at the edge of science over 50+ years. It's sad to see such a sudden end. There are three variants of radio-telescope design: 1. monolith dish (Arecibo or Green Bank) 2. Network of dishes (Very Large Array, or VLA, in New Mexico) 3. Network of individual dipoles (LOFAR in the Netherlands) One needs to combine all three in some ways to target different classes of astronomical problems. For example, if you want to understand the source structure, separate its left limb from the right, then you need smaller dishes separated by a large distance (like Very Large Array -- VLA). If you are looking at low frequencies of radio light, then you need dipole arrays like LOFAR. On the other hand if you are looking for giant burst of short-term energy, you are collecting light from a distant object. The more you collect, the better it is. So, single dish (or many dishes combined) works very well. Large single dish (Arecibo like) telescopes are also critical to characterize arrays like VLA or LOFAR. So, they are very useful still. Arecibo's success gave rise to improved design of a single mammoth dish telescopes in China (FAST). So, the design stays relevant and of importance. A new telescope called Square Kilometer Array (of size one square kilometer in effective area) would in principle replace a mammoth dish like Arecibo and tackle very diverse set of problems. However, Arecibo is like an old Volvo car that kept on going strong. You never want to junk such a old beauty even if you have a swanky Tesla standing outside your door, would you? Cheers!
  • sandworm101 6y ago
    I would add that the one thing arecebo had over fast was a transmit function, a suspended cabin heavy enough to support a radar emitter. If you want to bounce radar off planets, fast wont work.
    • asgekar 6y ago
      Correct! Bird lovers would hate to see those birds die, but the LiDar was the facility which allowed high-res atmospheric studies. FAST, or most other telescopes, don't have this capacity, especially with any comparable size (which allows us to amplify the signal when focused). Truly sad.