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China Businesses The Almighty Buck Technology

Tourism is Compromising the World's Largest Telescope (wired.com) 99

Posted by msmash from the upon-closer-inspection dept.
Thousands of people moved to let China build and protect Five-Hundred-Meter Aperture Spherical Radio Telescope (FAST), the world's largest telescope. And then the government drew in orders of magnitude more tourists, potentially undercutting its own science in an attempt to promote it. An excerpt: During the four-day Radio Astronomy Forum, Stierwalt and the other astronomers did, finally, get to see the actual telescope, taking a bus up a tight, tortuous road through the karst between town and telescope. As soon as they arrived on site, they were instructed to shut down their phones to protect the instrument from the radio frequency interference. But not even these astronomers, who want pristine FAST data for themselves, could resist pressing that capture button. "Our sweet, sweet tour guide continually reminded us to please turn off our phones," says Stierwalt, "but we all kept taking pictures and sneaking them out because no one really seemed to care." Come on: It's the world's largest telescope.

Maybe their minder stayed lax because a burst here or there wouldn't make much of a difference in those early days. The number of regular tourists allowed at the site all day is capped at 3,000, to limit RFI, and they have to put their phones in lockers before they go see the dish. Krco says the site bumps up against the visitor limit most days. But tourism and development are complicated for a sensitive scientific instrument. Within three miles of the telescope, the government passed legislation establishing a "radio-quiet zone," where RFI-emitting devices are severely restricted. No one (not cellular providers or radio broadcasters) can get a transmitting license, and people entering the facility itself will have their electronics confiscated.
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Tourism is Compromising the World's Largest Telescope More

Tourism is Compromising the World's Largest Telescope

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  • Telescope mode (Score:2, Funny)

    by Anonymous Coward

    Aren't these tourists using telescope mode on their phones?

    • AKA "Airplane mode"? Apparently not.

      (And the tour guide seem unaware of it)

      I'm sure even the tourists could understand the concept if it was properly explained to them.

      • Re: (Score:1)

        by Anonymous Coward

        Probably the processor processing data, updating the screen, the camera sending the image over the cable, etc. are sufficient to show up in the measurement with the phone close by.

    • Re: Telescope mode (Score:1)

      by Anonymous Coward

      It takes more than airplane mode. Your device radiates rf energy just simply running the cpu. Old style xenon camera flashes produce enormous bursts of wideband radio noise. Some radio telescope facilities only allow disposable 35mm film cameras.

    • Just buy the postcards you cheap fucks!

  • To limit RFI? (Score:2, Interesting)

    by thoughtlover ( 83833 )

    Yeah, that's what they invented Airplane Mode for. I can still use my camera without a single antenna turned on... maybe listen to some Yppah on my earbuds whilst enjoying the high desert air, to boot.

    • Plus: You'd think the siftware largest telescope in the world could filter out 3.5GHz during the daytime.

      • Nof if it wants to capture alien WiFi.

      • Plus: You'd think the siftware largest telescope in the world could filter out 3.5GHz during the daytime.

        So, scientists should just not observe the CH bond in molecular clouds, which has spectral lines at 3.4 GHZ because tourists want to gab on their phones?

        This assumes that all of the phones that tourists carry are precisely engineered to not emit any signals at all outside of their assigned band, an assumption that is known to be wrong. And it assumes that none of the tourists have multi-mode phones that are emitting at the wrong frequency. We are talking consumer electronics of every variety and quality and

        • Not sure why you specify "daytime".

          Because that's when the tourists are active.

          You know radio telescopes work in the day, right?

          You know they work much better at night, right? ie. Pointing away from the big yellow ball thing.

          And that if the object being observed in the sky is only above the horizon in daytime, that they have no choice but to observe it then, right?

          Sure, apart from the other choice, ie. wait six months (which is something that happens all the time in Astronomy because of the big yellow ball being in the way for half the year).

          • You know they work much better at night, right? ie. Pointing away from the big yellow ball thing.

            You know I'm always forgetting, so please remind me which frequency is "yellow" and where does that fall in the EM spectrum?

            FYI - radio emissions from the sun are extremely weak, and radio telescopes are using during daylight hours all the time

            • Re: (Score:1)

              by anoko ( 5045191 )
              Radio emissions from the sun are not at all weak -- at most frequencies the Sun is the brightest source in the sky, stronger than CasA and CygA. You are right that daytime observing is possible with radio telescopes, but night time data is generally more valuable.

        • So, scientists should just not observe the CH bond in molecular clouds, which has spectral lines at 3.4 GHZ because tourists want to gab on their phones?

          There's no question that the telescope needs a quiet space around it and needs to only be filtered based upon what it's looking at. But I think they might need to consider a "tourist area" which happens to be an RF absorbing cage. Having a terrestrial telescope does come with a few built in disadvantages. When it's also expensive and disruptive, that bag

        • This - but also. I work at MeerKAT, and our receivers can pick up the CPU clocks of cellphones (~1.4 GHz is quite common cellphone clock frequency, it also happens to be right where we want to observe), even when they're on flight-mode.

          Fortunately our facility isn't much of a tourist place.

    • Airplane mode does not turn off all of the antennas. GPS is still active on many phones even while in airplane mode.

      It does turn off antennas that transmit, although on many flights you can turn WiFi back on so you can pay $$$ to surf the web while flying.

    • Re:To limit RFI? (Score:5, Informative)

      by anoko ( 5045191 ) on Tuesday August 28, 2018 @06:14AM (#57209296)
      While turning a cellphone into airplane mode probably solves the problem for 90%, the digital electronics inside a cellphone that is turned on still cause some RFI. That's why for most radio quiet zones, electronic devices that need to enter the radio quiet zones are carefully tested / selected before bringing them on site.
      • If only we had invented a technology for taking pictures that didn't require batteries or circuits.
        • I think the old style flash is worse than a phone in flight mode

          • Re: (Score:2)

            by PPH ( 736903 )

            What kind of flash would I have to use to illuminate a 500 meter object?

            • I don't know, but I would really worry about the electromagnetic intereference when that capacitor discharges through that floodlight.
            • If only we had a ginormous fusion reactor casting light on if, but far enough away - say 93M miles or so.
      • There are two ways to build a radio telescope. One is to maximize its size by creating an interferometer [wikipedia.org]. This is done by mounting two or more radio dishes as far apart as possible, then synchronizing the signals they receive. That gives you the resolving power of a radio dish as large as the separation of the dishes. In other words, you get a radio telescope able to resolve extremely fine detail at radio wavelengths.

        The other is to maximize surface area. A circle actually has the smallest diameter

      • Re: (Score:1)

        by Anonymous Coward

        Radio astronomer here. I usually wouldn't worry about this. Most radio observatories have electronic equipment that hasn't been explicitly tested for RFI. It's usually only radio transmitters - phones, laptops with wi-fi, wireless mice, etc. - that are a problem. So setting phones to flight mode should be sufficient (though the tour guide may not have understood that).

        Some exceptions exist, though. Experiments trying to detect faint spectral signatures, like the epoch of reionisation, are more vulnerab

        • Re: (Score:1)

          by anoko ( 5045191 )
          Singe dish telescopes generally fall into the second category of observatories that are affected by low-level RFI, and I'm pretty sure that holds for FAST. But even for e.g. the Murchison RA observatory that only has interferometers, they do test equipment beforehand, because they are a problem. ( I'm also a radio astronomer )
    • Comment removed based on user account deletion

    • Yeah, that's what they invented Airplane Mode for. I can still use my camera without a single antenna turned on...Â

      But how can you get the selfie you just took on Facebook before everyone else if you do that? I mean what's more important here. Some silly science stuff, or getting more likes?

    • Re: (Score:2)

      by oic0 ( 1864384 )
      They should just have a detector on the busses that warns if a cell is broadcasting. Don't start rolling until the warning light goes off.... How hard is that?

  • people moved??? LOL (Score:5, Informative)

    by OzPeter ( 195038 ) on Tuesday August 28, 2018 @05:43AM (#57209216)

    Thousands of people moved to let China build and protect Five-Hundred-Meter Aperture Spherical Radio Telescope

    Orly?!?!? People in China moved because they are very nice and wanted to help out the government??!?!

    BWHAHAHAHAHAHA

    Now let's look at an actual quote from TFA (yeah, I know .. I actually read it. And emphasis is mine)

    The country even forcibly relocated thousands of villagers who lived nearby, so their modern trappings wouldn’t interfere with the new prized instrument.

    • Lots of countries force people to move so that they can build what they want

      • Re: (Score:2)

        by OzPeter ( 195038 )

        Lots of countries force people to move so that they can build what they want

        Yeah but msmash painted this one as a voluntary relocation.

    • Thousands of people moved to let China build and protect Five-Hundred-Meter Aperture Spherical Radio Telescope

      Orly?!?!? People in China moved because they are very nice and wanted to help out the government??!?!

      BWHAHAHAHAHAHA

      Now let's look at an actual quote from TFA (yeah, I know .. I actually read it. And emphasis is mine)

      The country even forcibly relocated thousands of villagers who lived nearby, so their modern trappings wouldn’t interfere with the new prized instrument.

      Possible non-evil explanation: What they meant was, "Thousands of people were moved ..."

      • Possible non-evil explanation: What they meant was, "Thousands of people were moved ..."

        Hold on, that would have made sense in a headline where "unnecessary" words are dropped all the time. But this was in the text, so ... yeah, that's bullshit.

  • Government Will Do Science When It Wants (Score:3)

    by careysub ( 976506 ) on Tuesday August 28, 2018 @06:28AM (#57209324)

    In an authoritarian state, that could forcibly relocate thousands to build the telescope, decides it wants to actually do science, as opposed to promoting its project, it can impose the effective EM silence that is needed. Simply enforce the existing no-electronics zone, collecting all non-conforming electronics at the zone edge. I am sure they can offer "selfie services" at the telescope for a price, downloadable at home. This is an easy fix for them.

    • Re:Government Will Do Science When It Wants (Score:4, Informative)

      by Anonymous Coward on Tuesday August 28, 2018 @06:54AM (#57209386)

      Nothing new here. At the Green Bank Observatory in West Virginia the tourist shop sells single use film cameras that are allowed to be used while in close proximity to the receiving dishes. Film cameras with analog light meters are the only ones allowed while close to the receiving dishes. Note that modern electronic devices emit low levels of microwave radiation while not intentionally transmitting. Airplane mode is simply not good enough.

  • rent out old SLR film cameras at the start of the tour.
  • And the lesson here is that you should build the world's SECOND largest telescope. Almost as good technically, and far fewer tourists.

    • Re: (Score:2)

      by GuB-42 ( 2483988 )

      Reminds me of a quote from Contact

      First rule in government spending: why build one when you can have two at twice the price? Only, this one can be kept secret.

    • And the lesson here is that you should build the world's SECOND largest telescope. Almost as good technically, and far fewer tourists.

      Didn't you read the article? The main point is not to do actual astronomy but to draw tourists to Astronomy Town nearby.

  • "Thousands of people moved to let China build and protect Five-Hundred-Meter Aperture Spherical Radio Telescope (FAST), the world's largest telescope"
    No that's not correct, thousands were dragged out of their homes in the wee hours of the morning just before the bulldozers flattened the house. If they dod leave the bulldozers flattened them anyway.

    • Reality check: the villagers were of course notified far in advance and offered 12,000-22,000 yuan cash or new housing as compensation. Many feel it wasn't fair compensation, and no doubt it wasn't for some since the payouts apparently didn't account for differing property values, but so it goes.

      • Thanks for the sanitized version.
        Does PRC shill work pay well?
        None of the news outlets report housing as compensation, or cash, just a check for $1800.
        What do you think happens to villagers who refuse to leave their house for $1800?
        Bulldozers at dawn...just like in Beijing.

  • Can someone explain why the scope doesn't seem to have anything in its focal point?

    • Re: (Score:2)

      by PPH ( 736903 )

      It does. A small receiver structure supported by cables from the surrounding towers. It's difficult to see in TFA pictures. Maybe someone should go there and snap some more.

  • Build and they will come, but leave your stupid phone at home. YEAH RIGHT. People would rather leave their kids/dogs/relatives in a car, than be without their phones for a few seconds. Personally, I'd rather have my good d-SLR, than a silly phone to take photos. Plus, they build this out in the middle of nowhere, to escape the RFI from towns, and now they are building up the area, and it will screw up the radio receiver. Good thinking!

  • ... as many pictures [blogspot.com] as I damned well please.

  • I suppose the only real solution is to put radio telescopes in places that no one wants to visit or is super difficult to visit.

  • Oh, just wok on in...

  • Set up a kiosk at the entrance to rent out Polaroid instant film cameras.

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