Follow Slashdot blog updates by subscribing to our blog RSS feed

 



Forgot your password?
typodupeerror
Space

Astronomers Use Black Holes to Pinpoint Earth's Location. But are Phones and Wifi Blocking the View? (space.com) 28

Measuring earth's position (or "geodesy") requires using telescopes that track radiation from distant black holes. Their signals "pass cleanly through the atmosphere and we can receive them during day and night and in all weather conditions," writes a senior scientist at the University of Tasmania.

But there's a problem... Radio waves are also used for communication on Earth — including things such as wifi and mobile phones... [A] few narrow lanes are reserved for radio astronomy. However, in previous decades the radio highway had relatively little traffic. Scientists commonly strayed from the radio astronomy lanes to receive the black hole signals. To reach the very high precision needed for modern technology, geodesy today relies on more than just the lanes exclusively reserved for astronomy.

In recent years, human-made electromagnetic pollution has vastly increased. When wifi and mobile phone services emerged, scientists reacted by moving to higher frequencies. However, they are running out of lanes. Six generations of mobile phone services (each occupying a new lane) are crowding the spectrum... Today, the multitude of signals are often too strong for geodetic observatories to see through them to the very weak signals emitted by black holes. This puts many satellite services at risk.

To keep working into the future — to maintain the services on which we all depend — geodesy needs some more lanes on the radio highway. When the spectrum is divided up via international treaties at world radio conferences, geodesists need a seat at the table. Other potential fixes might include radio quiet zones around our essential radio telescopes. Work is also underway with satellite providers to avoid pointing radio emissions directly at radio telescopes. Any solution has to be global. For our geodetic measurements, we link radio telescopes together from all over the world, allowing us to mimic a telescope the size of Earth. The radio spectrum is primarily regulated by each nation individually, making this a huge challenge.

But perhaps the first step is increasing awareness. If we want satellite navigation to work, our supermarkets to be stocked and our online money transfers arriving safely, we need to make sure we have a clear view of those black holes in distant galaxies — and that means clearing up the radio highway.

Astronomers Use Black Holes to Pinpoint Earth's Location. But are Phones and Wifi Blocking the View?

Comments Filter:
  • Radio silence please so we can spy on some black hoes.

  • I don't see this happening.

    • If there's a compelling need to allocate spectrum for astroradiology, there are mechanisms for this. The post cloyingly and insanely believes their need is compelling over all of the other allocations already made.

      There's a seat at the table available, but the process is well known, and their need isn't prioritized by the intense need to precisely correlate the earth's position in the universe by listening to black hole songs.

      • But how will we know where the satellites are if we don't know where the Earth is in relation to several distant blackholes? You can't track them without knowing the absolute position of the Earth. /s
      • If there's a compelling need to allocate spectrum for astroradiology, there are mechanisms for this. The post cloyingly and insanely believes their need is compelling over all of the other allocations already made.

        There's a seat at the table available, but the process is well known, and their need isn't prioritized by the intense need to precisely correlate the earth's position in the universe by listening to black hole songs.

        Exactly. One thing a lot of scientists run up against is their singular focus. The ITU and WRC has a good process, and with coordination, they can establish quiet zones that extend some area around specific sites. For grins, I like to show people the NTIA frequency allocation chart and ask them who they want to be kicked out to serve their needs - apparently these folk believe civilization is in danger of collapsing (FTA) if we don't kick everyone out of "their frequencies." https://www.ntia.gov/sites/def. [ntia.gov]

        • by jd ( 1658 )

          I disagree. First, the bands used for astronomy are regularly used by others, which is one reason why radio telescopes have radio silence zones. Second, astronomy certainly trumps the need for cat videos or porn. Thirdly, you really really don't need all the frequencies that are currently being used for domestic purposes, because they're being used very inefficiently. You can stack multiple streams onto far fewer lanes and use multiplexing. Fourthly, whingers lost any sympathy they might have got from me by

    • I don't see this happening.

      https://www.ntia.gov/page/unit... [ntia.gov].

      I don't either. And other countries are in a similar state.

      I printed out a full sized chart of those allocations, and hung it on my wall at one time, and when someone came in yapping about needing a place to park their transmitters, I'd ask them to find a place on the map. "Holy shit!" was a common response.

      And if they did point out some area, the nature of RF at that frequency made it a non-starter. RF is unruly, and acts completely different at different frequen

  • ...of moon to get enough quiet.

  • Earth's location...........with respect to WHAT? ..did I miss something? is humanity living in multiple locations?
    • Re: (Score:3, Informative)

      by necro81 ( 917438 )

      Earth's location...........with respect to WHAT? ..did I miss something? is humanity living in multiple locations?

      The summary (and article, too, I suppose) are sloppily written. They talk about geodesy, which is precise measurement of the Earth's shape - not position. Most folks know that the Earth is not a perfect sphere. It bulges by ~20 km radially at the equator (an oblate spheroid) due to rotation and tides. This is a pretty-good approximation for most purposes.

      But when you get precise enoug

  • If I am driving my car down a lane of traffic, but I veer into another lane, say of oncoming traffic, I'll get into a wreck and won't get to my destination.

    The answer to that is not to limit the traffic that is staying in their own lane that I veered into because I wanted more than I already have.

    I either have to stay in the lane(s) I have available or build new lanes.

    • by jd ( 1658 )

      Bad analogy, because science has no choice but to use the lanes that the signals are emitted on. You, on the other hand, can use absolutely any frequency you please. That won't affect you.

  • by topham ( 32406 ) on Monday July 28, 2025 @09:26AM (#65549880) Homepage

    This is fear monger ignorance.

    The type of data potentially collected this way is, of course, interesting, but it's the type of information that tells us the earth rotated a tiny bit faster on July 22nd, 2025 UTC.

    They haven't even fed that difference into the GPS. It might, possibly, make it into a future adjustment. The same adjustment they've been considering eliminating because it's pointless for the vast majority of use-cases. The value for that particular adjustment is so narrow the people generating the adjustment data are the only ones that use it.

    An article like this, glossing over specifics, it's one thing when it's written to bring in an audience, but the failure to be specific (no, generically pointing at cellphones and wifi is not specific) makes the article useless for a discussion.

    Somebody somewhere is looking to fund some research papers, instead they should find themselves out on their ass.

  • typical elite I know better nonsense...

"Indecision is the basis of flexibility" -- button at a Science Fiction convention.

Working...