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On Losing Arecibo

I always wanted to get to Arecibo, the magnificent 305-meter telescope that has for so long been a locus for radio astronomy research, but I was never able to make it to Puerto Rico. Now I’ve run out of time. The National Science Foundation doesn’t make these decisions lightly but multiple engineering companies have delivered assessments that point to catastrophic failure of the telescope structure as a real possibility. Too dangerous to repair, and faced with stability issues even if it could be repaired, the Arecibo Observatory will be decommissioned.

The breakdown in the vast structure has been ongoing, bits and pieces of news that added further dismay to an already dismal 2020. A support cable detached in August, resulting in an evaluation from the University of Central Florida, which manages the site. Replacement auxiliary cables were then on the way, temporary cables available, but on November 6 another main cable broke. The stresses on the second cable evidently told the story, making it clear that to proceed with repair would be to push against acceptable standards of safety.

Ralph Gaume, director of NSF’s Division of Astronomical Sciences, sums up the situation:

“Leadership at Arecibo Observatory and UCF did a commendable job addressing this situation, acting quickly and pursuing every possible option to save this incredible instrument. Until these assessments came in, our question was not if the observatory should be repaired but how. But in the end, a preponderance of data showed that we simply could not do this safely. And that is a line we cannot cross.”

Image: Arecibo Observatory’s 305-meter telescope in November of 2020. Credit: University of Central Florida.

It’s going to take some time for me to get my head around losing Arecibo, which has been since the early 1960s a part of my mental landscape when contemplating our civilization and its context in the cosmos. I had gotten to thinking in terms of ‘Arecibos’ of transmitting power, meaning that a dish like Arecibo could pick up an installation of comparable power over a span of 1,000 light years, a volume in which there are more than 10,000,000 stars. Ideas like that fueled my interest in SETI, which grew into a general passion for exoplanet research.

Remember, although we sometimes hear 51 Pegasi b referred to as the first exoplanet discovered, the honor actually belongs to the planets at the pulsar PSR B1257+12, which were found three years earlier in 1992 by Aleksander Wolszczan and Dale Frail using Arecibo data (51 Pegasi b was the first exoplanet found around a main sequence star, a valid distinction since pulsar planets are an unusual extreme as we contemplate the conditions extant in planetary systems). Speaking of pulsars, the first binary one was uncovered in Arecibo data in 1974 by Russell Hulse and Joseph H. Taylor, Jr., a find that earned the duo the Nobel Prize for Physics in 1993.

Arecibo has produced radar maps of Venus and Mercury and has charted near-Earth asteroids. As far back as 1965, it uncovered the actual rotation rate of Mercury (59 days as opposed to the previously believed 88). It analyzed the pulsar from the Crab Nebula supernova remnant in 1968 and performed the first radar ranging to an Earth-crossing asteroid (1862 Apollo) in 1980. Its planetary radar found evidence for hydrocarbon lakes on Titan and the observatory was used to study frequencies in the 1,000 MHz to 3,000 MHz range as part of the SETI effort.

Indeed, the list of accomplishments is far too long to list here, so I’ll direct you to this summary page. I do want to mention in the SETI context (although it was a matter of transmitting rather than listening) the 1974 message sent toward the globular cluster M13 by Frank Drake, primarily performed, I’m told, as a way of demonstrating what newly installed equipment could do. Even so, that transmission is an oft-cited marker in our thinking about our own place in the universe and the possibility of other technological civilizations we might encounter.

Invariably I think of Jill Tarter in terms of SETI, in this context because of her involvement in Project Phoenix, which moved to Arecibo in 1998 after stints at Parkes (Australia) and Green Bank (WV). As soon as I learned of Arecibo’s decommissioning, I wrote to ask for a comment. My own reflections on Arecibo hardly match the poetic depth of Dr. Tarter’s response:

I’ve been going to Arecibo since 1978. Over the decades, we’ve built a lot of Arecibo-specific hardware, written a lot of software, and bent the telescope control system into modes it was never designed for.

Arecibo was an impressive feat of engineering, a scientific workhorse, and it never lost that aura of being slightly exotic, no matter how many times I visited there; the constant croaking of the coquis [a frog common to Puerto Rico], the perfumes of the tropical forest, the local Ron del Barrelito [a rum said to be the best on the island], the Gregorian dome with its unmistakable compressor cadence, the jogging track underneath the dish ringed with small orchids, Orion rising over the treetops as seen from the balcony of the VSQ [Visiting Scientists Quarters], before heading off to my midnight shift of Project Phoenix observations, and the absolutely best view on the island from atop the platform.

But most of all I remember the staff and the resident scientists who were very close knit, offered us superb technical support, and threw wonderful parties with lots of dancing. It is very sad to witness the passing of this scientific Queen. She withstood powerful hurricanes, but age appears to have gotten the upper hand.

Arecibo’s demise also led me to touch base with Greg Matloff (New York City College of Technology (NYCCT)), whose work on interstellar propulsion was what originally drew me to the field (his Starflight Handbook, written with Eugene Mallove, was a frequently consulted text and provoked the research that led to my Centauri Dreams book in 2004). We had discussed Arecibo’s role in planetary protection in many conversations. Said Matloff:

“The loss of Arecibo is heartbreaking. This observatory has contributed so much to the study of Earth’s upper atmosphere, Solar System and deep sky objects, and SETI. But its greatest significance today is its service as planetary radar. Much of what we know about Near Earth Asteroids that might someday impact the Earth is due to the imaging capabilities of this instrument. It is my hope that an upgraded Arecibo can be constructed at the same site to continue this work of Earth Defense.”

That’s a hope many of us share, and we will see what comes of it. I do notice in the National Science Foundation’s materials on the decommissioning that NSF intends “to restore operations at assets such as the Arecibo Observatory LIDAR facility — a valuable geospace research tool — as well as at the visitor center and offsite Culebra facility, which analyzes cloud cover and precipitation data. NSF would also seek to explore possibilities for expanding the educational capacities of the learning center.”

What may emerge following telescope decommissioning is worth pondering.


Comments on this entry are closed.

  • Thomas R Mazanec November 20, 2020, 10:34

    At least there is Tianyan in China to carry on the torch.

    • Jose December 5, 2020, 21:10

      Not sure if Tianyan FAST can track near Earth asteroids.

  • Hal Schirmer Esq November 20, 2020, 10:44

    It’s NOT lost. We know exactly where it it.
    It requires replacing 2 steel cables.

    That will cost, eh, 1% of the revenue that Facebook or CNN or MSNBC makes today?

    • Jake B November 24, 2020, 8:36

      I wish it were that easy. Unfortunately failure of two cables is the least of the sites issues. First is the safe re-installation of the support cables. Having work crews on the unstable platform to install new cables is a serious risk to life (and a gamble none would be willing to make) due to the below issues.
      The unfortunate fact is as such: corrosion and failure of the support structure is not limited to just one cable or tower. Each and every cable on the site has been neglected for at least a decade now. With two failed cables, the remaining cables are supporting an increased load with the same decaying hardware and structure. If anything else, the time to subsequent failure has been shortened by the loss of two cables.
      Another issue the site is having is the load at which the second cable failed. From what I heard (I’m sure there was an article on it somewhere), the second cable failed at 66% of it’s installed capability. This could indicate the site is closer to failure than originally thought and only one or more cables failing (which is more likely now due to the increased load) to total structural failure. This also means that every cable would need to be replaced or risks mitigated to become safe again.
      The final factor that we have to keep in mind is that the platform isn’t the same mass as built. The platform underwent a retrofit to install the geodesic dome which added a load significant enough to warrant the installation of additional support cables. With the suspected decrease in safe working load of the support cables, the tolerance of available load (factor of safety) is too small to safely begin repairs.

      Overall, engineers have likely deemed the risks to life and instability of the structure too great to warrant attempts to recover the aging equipment.
      It is a shame to see it go, but after looking at the situation I’d say it is the most responsible course of action.
      Our only hope now is that the need for the equipment will be enough to construct a new radio telescope to fill its role.

      • Kevin Herron November 29, 2020, 23:53

        When you don’t even try, failure is inescapable. I don’t buy your argument for a second. We have the capacity, capability, and (usually) the spirit and will to rise to the challenge. In this case, defeat was the accepted position without even trying. It can ALWAYS be rebuilt. ALWAYS. When your first inclination is to just shrink and accept failure – failure will ALWAYS, 100% of the time, be the result. That this facility was so neglected gor so long is an absolute, inescapable, crime, and those responsible should be fully held accountable. This facility has delivered so much gor so long, that what has happened is criminal.

        • Liam P December 1, 2020, 20:39

          The collapse of the receiver structure on Monday proves the point that Arecibo was beyond rescue at this point, and the decision to decommision it was sad but wise. The question to ask is why such deterioration was allowed to happen undetected till now in the first place.

    • James Jason Wentworth December 8, 2020, 19:55

      Krakan! (Anyone puzzled by this should read Arthur C. Clarke’s short story–and later, full-length novel–“The Songs of Distant Earth.”) The novel’s cover shows Arecibo’s Thalassan–and even more bucolically situated–cousin.

      The Arecibo radio/radar telescope actually did us a favor by demolishing itself, thus eliminating the tricky task of having construction workers do it–and live to tell about it. Bombing it with military aircraft (perhaps as part of crew training, just as the U.S. Army recovers sounding rocket payloads launched from Alaska’s Poker Flat Research Range as part of their Arctic training exercises) might have been the only safe alternative. (Today’s precision-guided weapons would have avoided hitting nearby buildings, which would have been evacuated to absolutely ensure that no one on the ground would have been at risk.) Also:

      A radio and/or radar telescope of this type only needs two things–a suitably-contoured hole in the ground and a cable-supported antenna carriage. (The first antenna of this type–much smaller than Arecibo’s, of course–was built by either the U.S. Army or the U.S. Navy [I forget which] in 1950 for Moon bounce communication experiments; a 50-foot wide hole was dug and lined with foil, with an antenna feed set up at the focal point or “focal line” [like Arecibo’s, its reflector may have been a portion of a sphere rather than parabolic in shape].) Now:

      The largest portion of the Arecibo telescope, the suitably-contoured hole in the ground (a natural hollow that was “finished” to the desired shape using earthmoving equipment) is still there, and suffered little or no damage from the collapses of the antenna carriage and tower portions (one tower collapsed in its entirety, falling across a nearby road). As well:

      A new Arecibo telescope could be started, on a “go as you pay” basis, by lining the hollow with wire mesh (as originally built, that was its reflector; the sectional aluminum sheets reflector was installed in the mid-1970s). The most “popular” mesh size (based on the most-used radio and radar frequencies, down to the minimum desired wavelength) could be selected by a users’ survey. It might be practical to make the reflector a parabolic one (properly-shaped support ribs would be needed), as this would eliminate the need for the Gregorian sub-reflector (or the previously-used long antennas) on the antenna carriage. But if not, it would be no “show-stopper” to use a newly-built, section-of-a-sphere reflector, as the telescope always has, and:

      A new, lighter antenna carriage could be built, out of composites and/or titanium, and the new multi-stranded support cables could be made of carbon fiber or some aramid fiber, such as Kevlar. The existing steel-reinforced concrete cable and antenna feedline (waveguide) support towers could be replaced with new ones, made of stainless steel and/or titanium, and they could be reinforced by outward-running, tensioned stays (which could also be of carbon or aramid fiber).

  • Joe H. November 20, 2020, 13:44

    I know it’s merely coincidence the structural problems of the aging telescope have come to light during this plague year. And yet in some ways Arecibo seems to reflect greater themes of decline and decay. The scientist/historian Peter Turchin is the latest in a long line of pessimistic prophets.


    How long before someone Photoshops a fallen Arecibo with the jungle encroaching, and lyrics of Ozymandias superimposed on the scene?

    • Paul Gilster November 20, 2020, 15:59

      Also eerily reminiscent of such J. G. Ballard stories as “The Dead Astronaut,” etc.

  • Patient Observer November 20, 2020, 14:38

    Sad, but good things die of old age if fortune is good. However, the pioneering concept is reincarnated in China:


  • Alex Tolley November 20, 2020, 15:51

    I am in two minds about this. Arecibo is an instrument from the past. If it truly has advantages over newer approaches, the Chinese have just finished their own version that eclipses Arecibo in size, and presumably in performance.

    I recently watched the Seti Institute live webinar on the future of telescopes, primarily about distributed radio telescopes. The speakers were unanimous is stating this was the future – lots of cheap receivers whose signals could be combined to make a very powerful radio telescope.

    If they are correct, venerating Arecibo is rather like fetishizing an IBM 360 mainframe computer despite computing replacing such machines with racks of cheap computers in server farms, and even distributing computations out to the “edge”.

    Brits still venerate steam engines like the “Royal Scotsman” even though the age of steam is long over and been replaced by diesel and electric trains. Many people still prefer the elegance of sailing ships over modern cargo ships that eschew wind power. There are those who still enthuse over the Saturn V rocket, even though it has long gone and newer rockets will likely surpass its performance.

    There is also a sadness in that it was a historic telescope, shown in relevant movies like “Contact”, and also as a backdrop in the James Bond movie – “Goldeneye”. It is as famous in its way as the 200 inch Hale telescope at the Palomar Observatory.

    One day the age of rockets soaring into the sky will end, replaced by far more elegant approaches of reaching orbit and traveling beyond to deep space. Yet many will still pine for the spectacle of the rocket age, with pictures and paintings adorning offices and living rooms with scenes of fiery takeoffs. And like Picard gently touching the Phoenix, we still haunt aerospace museums and marvel at aircraft from the first half-century of flight.

    • Henry Cordova November 20, 2020, 18:38

      The theoretical performance of any telescope, radio or optical, is determined solely by its aperture. You can upgrade an instrument by increasing the sensitivity of its detectors, or the precision of its mounting, or by resilvering or coating its surface. But once the accuracy of its lens or mirror’s figure relative to the wavelength it operates at is optimized, it cannot be fundamentally improved upon. There are optical telescopes well over a century old today which can still do valuable research, although they may have been overhauled mechanically and electronically several times since their “first light”. The 100″ Hooker reflector was not scrapped the day the 200″ Hale opened. In fact, the Mt Wilson instrument boasts a better paraboloid than the Palomar Telescope. For the same reasons, radio telescopes can be upgraded to modern specs, and even if they are eclipsed by bigger instruments today, they can still be useful in applications where sheer size is not critical. The major advantage of the Arecibo dish was the geological feature over which it was constructed. Unless this can be duplicated cheaply somewhere else, there may be very good reason to repair the old girl rather than build a replacement at another site.

      It may be that the collapse of the structures suspended over the mesh disk may have damaged it so much that it can no longer be economically or safely repaired. If that is the case, then so be it. But age or technological obsolescence alone is not sufficient reason to abandon the site.

    • David November 21, 2020, 1:49

      There will always be a need for single dish antennas such as Arecibo because they will detect radiation that will be missed by aperture synthesis telescopes such as the VLA or ALMA. The latter do not detect radiation at all spatial scales, particularly from sources that are extended in size.
      If you want more see: http://articles.adsabs.harvard.edu//full/2002ASPC..278…27E/0000034.000.html

    • Alex Tolley November 21, 2020, 15:28

      @Henry, @David

      If I have misunderstood this SETI talk then I stand corrected. However, the 2 speakers appear to me to be saying that multiple, linked, receivers in arrays, like the SKA, are far more sensitive AND have a better field of view than the largest single-dish radio telescopes, AND that they are steerable too. I certainly do not have the expertise to tell if what they are saying is misleading, but I trust the SETI organizers to put on speakers who are credible experts.

      Radio Astronomy: The End of Big Dishes?

  • ole burde November 20, 2020, 16:26

    Responsible maintenance is to keep ´´the old one´´ working , NO MATTER WHAT , until ´´the new one ´´ is a certified sucses ……but thats just oldfashioned little me , grandfather-talk

  • charlie November 20, 2020, 17:45

    “Its planetary radar found evidence for hydrocarbon lakes on Titan …” , Is that true ? This radio telescope ACTUALLY was able to detect a liquid hydrocarbon Lake on a tiny moon like Titan? That seems like an awfully small target as well as a extremely distant one. How did it manage that feat?

  • Michael Fidler November 21, 2020, 4:14

    We can put the blame on many things but global warming has caused more problems around the globe at many observatories. The hurricanes and wild fires have destroyed or have come close to destroying many observatories and it is only going to get worst. Sad we live in such conflicting days.

  • Henry Cordova November 21, 2020, 13:58

    In praise of the “Starflight Handbook”

    I too have a copy of the Matloff/Mallove work, and it is indeed a useful and oft-consulted reference.

    But my copy was published in 1989, over thirty years ago! It must be way out of date. Surely there has been much progress in this field since it appeared. Are there any newer, revised editions available, or any other comparable volumes which examine this field for today’s readers?

    • Paul Gilster November 21, 2020, 21:42

      I wish we could get Wiley to publish a new edition of The Starflight Handbook, but evidently it won’t happen. Kelvin Long wrote Deep Space Propulsion in 2011 (it’s a Springer title). Like the Matloff book, it offers a wide survey of the available technologies. Greg’s Deep Space Probes is invaluable and in its second edition.

  • Alex Tolley November 21, 2020, 19:24

    SETI Institute: Tour the Arecibo Telescope youtube video.

  • safely anon November 21, 2020, 21:43

    Keep up the good work Paul & everybody, I’ve appreciated the last several posts.

    The loss of Arecibo I don’t understand. It would be one thing if they were to say that we don’t need it anymore because it fulfilled its mission, but just saying it can’t be repaired? That’s not much to go on. How was it constructed? What’s the wider context on its usefulness in the future? I see some disagreements about this above in the comments but it would be nice to have a more reputable source!

    • Henry Cordova November 22, 2020, 16:48

      I may not be a “reputable source”, but here’s what I know about the Arecibo Instrument.

      The stationary 1000 foot parabolic dish takes advantage of a natural sinkhole in the limestone of that part of the island. The towers that suspend the transmitter/receiver at the focus of the parabola can (to a certain extent) “steer” the dish by moving the focus around, using long movable cables. They are conveniently perched on hills surrounding the depression. Although the instrument was originally designed for ionospheric studies, directly overhead, the “beam” can be pointed in different directions, albeit at some loss of effective aperture. The dish is wire mesh suspended in the sinkhole, shimmed up in order to provide the appropriate parabolic figure.

      Its a clumsy arrangement, but its a 1000 foot dish, the largest in the world, without the complex, expensive and delicate altazimuth mount required for a fully steerable antenna. Its radio-quiet remote location and low latitude allow it to cover large areas of the celestial sphere.

      No doubt Arecibo could be rebuilt somewhere else, but it will be expensive. I know nothing about the Chinese alternative being constructed now.

  • Jeff Brandt November 22, 2020, 1:48

    I reside in Puerto Rico and there is a chance to save it! We just need to convince the NSF to relinquish control to the UCF, UAGM, NASA and other interested parties and allow them to continue without dependence on NSF funding. The Army Corp of Engineers is willing to attempt the repair. The new cables, already bought and paid for. Our representative just sent a letter to Congress asking for intervention.


  • xcalibur November 22, 2020, 12:13

    It’s bittersweet when things come to an end. I understand that Arecibo did alot of good work and had a long run; on the other hand, safety must come first. perhaps it can be rebuilt better than before, who knows? what matters most is that we continue to further our understanding of the cosmos, whatever it takes.

  • Afterthought November 22, 2020, 22:46

    Build one in a crater on far side of the moon.


  • Richard November 23, 2020, 20:36

    Sooner or later, one of these was going to need to be dismantled. Perhaps another powerful may be built. Perhaps orbital based telescope would be better.

  • Wilfredo Molina November 24, 2020, 23:26

    It is a true legend that will never be forgotten. I hope that from the ashes of our great structure a new and more advanced arecibo will rise in its place.i look forward to seeing this wonder happen in my lifetime.

  • Jessica Martinez November 25, 2020, 8:17

    I came here and it was amazing. But to see something so important to be removed because it can’t be fixed it’s mind blowing to me. With all the technology we have it can’t be fixed. Makes no sense at all. One more thing we are giving China…. thanks 😠

  • Rajasekar November 25, 2020, 9:20

    I believe in Science, Engineering and Technology.

    The Scientific Community should not lose this great facility.
    So many developments have happened in the last few decades; Miniature electronics, Smart and advanced materials, analysis tools, erection and material handling equipments,etc.

    It’s possible.
    Scientists and engineers, please rise to the occasion.
    Join hands with experts throughout the world.
    Hurry up.

  • Margarita Ilecki November 25, 2020, 16:25

    I am in agreement with Henry Cordova. If the destruction of the Arecibo telescope site is not a “fete accompli,” I will join in any fund raising effort to save save this useful and historically important research telescope.

  • Dora Maya November 29, 2020, 16:15

    Why not repair/replace with 21 century technology?

  • ljk January 4, 2021, 11:19

    JANUARY 3, 2021

    A Puerto Rican Scientists Mourns the Loss of a Legendary Telescope
    Hurricanes, earthquakes, and now this.


  • ljk January 4, 2021, 11:24

    Arecibo Telescope Awarded $8 Million for Possible Reconstruction

    Could this initial funding inspire potential U.S. sponsors to donate the rest?

    By Loukia Papadopoulos

    January 01, 2021


  • ljk January 14, 2021, 15:28

    Frank Drake’s daughter Nadia writes about the very personal effects of the loss of Arecibo:


    Includes photographs I am sure few outside of the Drake family have ever seen before.

  • ljk January 15, 2021, 15:00

    How the famed Arecibo telescope fell—and how it might rise again

    By Daniel Clery

    Jan. 14, 2021, 11:52 AM

    In the early morning of 10 August 2020, Sravani Vaddi, a postdoc astronomer at the Arecibo Observatory in Puerto Rico, was working from home, but her thoughts were at Arecibo’s giant radio telescope. At 2 a.m., she had one precious hour to focus the 305-meter dish on NGC 7469, a distant galaxy.

    At its center, two supermassive black holes wheeled around each other, following an earlier galaxy merger. Vaddi wanted to see whether having two dark hearts instead of the usual one made the galaxy shine more brightly by stirring up gases and stoking starbirth. Radio emissions from the glowing gases would help her find out.

    When she checked in near the end of her observations, computer servers suggested the telescope wasn’t pointing at the galaxy anymore. She couldn’t get an on-site telescope operator on the phone, so she gave up and went to bed.

    She woke up to a full inbox. At 2:45 a.m., toward the end of her slot, an 8-centimeter-thick steel cable, one of 18 suspending a 900-ton instrument platform high above the dish, had pulled out of its socket at one end and fallen, slicing into the dish. “I was totally shocked. How could a cable break?” she says. Although she didn’t know it at the time, the photons she gathered from NGC 7469 would be the last ones Arecibo would ever scoop up.

    The rest of the story is now well known. A second support cable snapped 3 months later, on 6 November, and the National Science Foundation (NSF), which owns the observatory, said attempting repairs was too dangerous: Arecibo would be dismantled. On 1 December, fate took control as more cables snapped and the platform, as heavy as 2000 grand pianos, came crashing down into the dish.

    Full article here:


    To quote:

    Along with the grief have come sharper questions. After surviving numerous earthquakes and hurricanes, why did this scientific crown jewel collapse so unceremoniously on a calm winter morning? Some engineers and astronomers think manufacturing flaws or poor maintenance in a tropical, corrosive environment doomed the suspension cables. Others place blame at the feet of NSF’s astronomy division, which for more than a decade tried to offload Arecibo so it could divert funds to operating newer telescopes. “Somehow, we lost a $300 million instrument, a magnificent, really expensive instrument, for a few million dollars,” says Richard Behnke, an Arecibo staffer from 1970 to 1982 who went on to head the geospace science division at NSF. “Things should not collapse like that. It’s not acceptable stewardship at all.”

    Meanwhile, astronomers are looking to the future. “First we mourned, then we had a wake, then we got down to work,” says Joanna Rankin, an astronomer at the University of Vermont. Together with Arecibo staff, researchers last month delivered a white paper to NSF describing plans for a new $400 million telescope on the same site. Although any rebuilding effort faces major political and financial hurdles, the proposal aims for an instrument with even more dazzling capabilities than the one that was lost. “There’s been a remarkable amount of commitment and energy,” Rankin says.

  • ljk January 15, 2021, 17:41



    JANUARY 13, 2021

    Scientists outside China will be allocated around 10% of observation time on its gigantic radio telescope following the collapse of Arecibo.

    China is making its Five-hundred-meter Aperture Spherical Telescope (FAST) available to international scientists in the wake of the collapse of the Arecibo telescope in Puerto Rico late last year.

    The National Astronomical Observatories of China (NAOC), the telescope’s operator, confirmed on January 4th that scientists outside of China will be able to apply for time using the facility on April 1st. A timetable for observation will then be published by August 1st.

    Full article here:


  • ljk January 24, 2021, 22:42
  • ljk January 25, 2021, 22:49

    Preliminary investigation offers possible cause of Arecibo Observatory telescope collapse

    By Meghan Bartels 14 hours ago


    To quote:

    And the answer may never be crystal clear. “Certainly, there’s typically not a single item that contributed but a multitude of items that contributed to the particular failure,” Cordova said. In addition to the facility’s age, the past few years have been hard on Puerto Rico. In 2017, Hurricane Maria battered the island, and over the course of 2020, it experienced more than 10,000 earthquakes.

    “Basically, we were shaking the entire time; that certainly could have been a factor,” Cordova said. “That’s being still analyzed by the engineering teams.”

  • ljk March 3, 2021, 17:12


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

    Press Release – Source: astro-ph.IM

    Posted March 2, 2021 11:55 PM

    Figure caption:

    An array of 1,112 dishes of 9 m in diameter within a ~314 m diameter circle is shown on the left. The number of dishes could be reduced by increasing the dish diameter, as shown in the right figure where an array of 400 dishes of 15 m diameter within a 331 m diameter circle. In both cases, the array will provide an equivalent collecting area of a 300 m diameter dish. It is evident that the packing efficiency is not optimum when the diameter of the dish is increased. Dishes with hexagonal shape could be considered during the engineering study to investigate whether higher collecting area can be achieved with less number of dishes.

    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.

    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

    Comments: 82 pages (executive summary 10 pages), 21 figures, Arecibo observatory white paper

    Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR); Atmospheric and Oceanic Physics (physics.ao-ph); Instrumentation and Detectors (physics.ins-det)

    Cite as: arXiv:2103.01367 [astro-ph.IM] (or arXiv:2103.01367v1 [astro-ph.IM] for this version)

    Submission history

    From: D. Anish Roshi

    [v1] Tue, 2 Mar 2021 00:04:14 UTC (6,883 KB)



  • ljk March 9, 2021, 12:55

    Arecibo Observatory has more science to do despite iconic radio telescope’s collapse

    By Meghan Bartels a day ago

    Arecibo Observatory must scientifically reinvent itself even as it continues mourning its iconic radio telescope and cleaning up its debris.


    The main dish may be down, but Arecibo has other scientific instruments that survived and are still working.

  • ljk March 22, 2021, 10:51

    Work Begins on Cleaning up Arecibo. The job Could Cost $50 Million

    MARCH 20, 2021



    Probably would have cost much less if the NSF had bothered to properly fund Arecibo over the last few decades, rather than playing games with the money for it – constantly threatening to take away all funding for the observatory multiple times.

    This is what happens when you have a culture that focuses on the bottom line over everything else.

  • ljk April 1, 2021, 11:38

    Legacy of shattered alien-seeking Arecibo telescope will live on for millions of years

    By Mindy Weisberger 4 days ago

    “Lost, not forgotten.”

    The Arecibo Observatory radio telescope in Puerto Rico, which made Earth’s first attempt to contact aliens, shaped pioneering cosmic research for nearly six decades. Its collapse in December last year, preceded by two cable failures and the National Science Foundation’s (NSF) decision to decommission and dismantle the telescope, marked the end of an era.

    Nevertheless, Arecibo leaves behind a rich legacy of scientific discovery spanning 57 years, and data collected prior to the telescope’s demise will continue to inform the study of asteroids, planets and distant galaxies, researchers recently reported.

    Scientists outlined Arecibo’s enduring contributions to radio astronomy in a presentation on March 19 at the 52nd Lunar and Planetary Science Conference (LPSC), held virtually this year due to the COVID-19 pandemic. The presenters wrote that Arecibo left an “indelible mark on planetary science, radio astronomy, and space and atmospheric sciences,” and they expressed the sorrow surrounding its collapse in a wistful haiku:

    “Six decades’ service / Arecibo’s telescope / Lost, not forgotten.”

    Full article here:


    To quote:

    But the most long-lived part of Arecibo’s legacy may be the Arecibo Message, which will keep moving long after generations of scientists have combed through all of the telescope’s data. The message is traveling at the speed of light toward its target — a cluster of 300,000 stars about 25,000 light-years (about 150 quadrillion miles, or nearly 240 quadrillion kilometers) from Earth; even after it reaches its destination, the message will continue its journey into outer space, perhaps for millions of years, the Cornell Chronicle reported in 1999, on the 25th anniversary of Arecibo’s landmark broadcast.