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Thread: Broken Cable Damages Arecibo

  1. #61
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    Quote Originally Posted by cjameshuff View Post
    If any part's ever been a good parabola, it's been by accident...it's a spherical dish.
    Oops
    sicut vis videre esto
    When we realize that patterns don't exist in the universe, they are a template that we hold to the universe to make sense of it, it all makes a lot more sense.
    Originally Posted by Ken G

  2. #62
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    Quote Originally Posted by profloater View Post
    Oops
    Well spherical is good for my proposal to use a drone, the spherical aberation stays about the same for different focus lateral points.
    sicut vis videre esto
    When we realize that patterns don't exist in the universe, they are a template that we hold to the universe to make sense of it, it all makes a lot more sense.
    Originally Posted by Ken G

  3. #63
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    An intriguing proposal to rebuild the Arecibo radio telescope even better than before.

    The Future Of The Arecibo Observatory: The Next Generation Arecibo Telescope.

    D. Anish Roshi, N. Aponte, E. Araya, H. Arce, L. A. Baker, W. Baan, T. M. Becker, J. K. Breakall, R. G. Brown, C. G. M. Brum, M. Busch, D. B. Campbell, T. Cohen, F. Cordova, J. S. Deneva, M. Devogele, T. Dolch, F. O. Fernandez-Rodriguez, T. Ghosh, P. F. Goldsmith, L. Gurvits, M. Haynes, C. Heiles, D. Hickson, B. Isham, R. B. Kerr, J. Kelly, J. J. Kiriazes, S. Kumar, J. Lautenbach, M. Lebron, N. Lewandowska, L. Magnani, P. K. Manoharan, S. E. Marshall, A. K. McGilvray, A. Mendez, R. Minchin, V. Negron, M. C. Nolan, L. Olmi, F. Paganelli, N. T. Palliyaguru, C. A. Pantoja, Z. Paragi, S. C. Parshley, J. E. G. Peek, B. B. P. Perera, P. Perillat, N. Pinilla-Alonso, L. Quintero, H. Radovan, S. Raizada, T. Robishaw, M. Route, C. J. Salter, A. Santoni, P. Santos, S. Sau, D. Selvaraj, A. J. Smith, M. Sulzer, S. Vaddi, F. Vargas, F. C. F. Venditti, A. Venkataraman, A. K. Virkki, A. Vishwas, S. Weinreb, D. Werthimer, A. Wolszczan, L. F. Zambrano-Marin

    The Arecibo Observatory (AO) is a multidisciplinary research and education facility that is recognized worldwide as a leading facility in astronomy, planetary, and atmospheric and space sciences. AO's cornerstone research instrument was the 305-m William E. Gordon telescope. On December 1, 2020, the 305-m telescope collapsed and was irreparably damaged. In the three weeks following the collapse, AO's scientific and engineering staff and the AO users community initiated extensive discussions on the future of the observatory. The community is in overwhelming agreement that there is a need to build an enhanced, next-generation radar-radio telescope at the AO site. From these discussions, we established the set of science requirements the new facility should enable. These requirements can be summarized briefly as: 5 MW of continuous wave transmitter power at 2 - 6 GHz, 10 MW of peak transmitter power at 430 MHz (also at 220MHz under consideration), zenith angle coverage 0 to 48 deg, frequency coverage 0.2 to 30 GHz and increased FoV. These requirements determine the unique specifications of the proposed new instrument. The telescope design concept we suggest consists of a compact array of fixed dishes on a tiltable, plate-like structure with a collecting area equivalent to a 300m dish. This concept, referred to as the Next Generation Arecibo Telescope (NGAT), meets all of the desired specifications and provides significant new science capabilities to all three research groups at AO. This whitepaper presents a sample of the wide variety of the science that can be achieved with the NGAT, the details of the telescope design concept and the need for the new telescope to be located at the AO site. We also discuss other AO science activities that interlock with the NGAT in the white paper.

    https://arxiv.org/abs/2103.01367
    Do good work. —Virgil Ivan "Gus" Grissom

  4. #64
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    The many small dishes approach probably makes good sense for economic and maintenance reasons. Without thinking about budget or other practical issues, I can imagine rebuilding it with a deformable dish that can change to maintain a parabolic section keeping the same spot in the sky in focus for an hour or so. This would be MUCH more complex for the dish, but the transmitter/receiver would be greatly simplified, and the towers and cable would need to be about 1% as strong as the old ones were. Making the cables out of something that doesn't corrode so quickly would be expensive, but would be another plus.
    Forming opinions as we speak

  5. #65
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    Quote Originally Posted by antoniseb View Post
    The many small dishes approach probably makes good sense for economic and maintenance reasons. Without thinking about budget or other practical issues, I can imagine rebuilding it with a deformable dish that can change to maintain a parabolic section keeping the same spot in the sky in focus for an hour or so. This would be MUCH more complex for the dish, but the transmitter/receiver would be greatly simplified, and the towers and cable would need to be about 1% as strong as the old ones were. Making the cables out of something that doesn't corrode so quickly would be expensive, but would be another plus.
    What they propose sounds like the equivalent of building a giant pointable dish, and then covering it with smaller dishes. I'm not sure how that's better for cost or maintenance. A compact array doesn't have the resolution advantage of phased arrays, while having all the disadvantages, such as greatly multiplying some of the pricier bits of hardware required.

    Maybe they'd be able to get more funding due to ability to track more flexibly and do simultaneous observations of different parts of the sky?

  6. #66
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    A report by the National Science Foundation estimates it will cost up to $50 million to clean up the damage from the collapsed Arecibo radio telescope, but that it is still too soon to determine whether or how to rebuild the famous observatory.

    https://spacenews.com/nsf-report-est...to-50-million/
    Do good work. —Virgil Ivan "Gus" Grissom

  7. #67
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    This lunar telescope could pull back the curtain on the cosmic dark ages

    https://news.yahoo.com/lunar-telesco...201500228.html

    adio telescopes are very useful for exploring the farthest reaches of the cosmos. This is because radio waves can slip past most obstacles, such as dust, which can scatter shorter wavelengths of light. However, there are three significant obstacles to using radio telescopes to explore the universe.

    The first is the nature of the radio waves themselves. The farther radio waves travel through space, the more they become stretched out. That is, their wavelength becomes longer. So, to gather radio waves from objects really far away, astronomers need to build larger and larger telescopes. The Arecibo telescope in Puerto Rico was a little over 300 metres wide. China's new FAST radio telescope has a diameter of 500 metres, and Russia's RATAN-600 spans over 570 metres wide. The larger the telescope, the longer the wavelength of radio waves that can be collected. Thus, the farther away, and the farther back in time, you can look.

    The second obstacle is Earth's atmosphere. As light falls on Earth from space — from gamma rays all the way to the longest radio waves — the atmosphere acts as a filter. There is a specific 'window' for radio waves, between around 1 millimetre up to just over 10 metres. These wavelengths can make it to the ground, but the rest is blocked out by Earth's ionosphere. Building your telescope higher up in the atmosphere, such as on a mountain top, can unlock some of the lower wavelengths, but not the higher ones.
    Priceless Astronomy Data Saved After Collapse of Arecibo
    https://news.utexas.edu/2021/05/10/p...ibo-telescope/
    Last edited by Launch window; 2021-May-17 at 07:20 PM.

  8. #68
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    Quote Originally Posted by Launch window View Post
    This lunar telescope could pull back the curtain on the cosmic dark ages

    https://news.yahoo.com/lunar-telesco...201500228.html
    What does that have to do with Arecibo?

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