Satellite Snoopers Pick Up Surprising TV Broadcast

While Internet based streaming services appear to be the future of television, there are still plenty of places where it comes into the home via a cable, satellite, or antenna connection. For most satellite transmissions this now means a digital multiplex carrying a host of channels from a geostationary satellite, for which a set-top box or other decoder is required. Imagine the surprise of satellite-watchers than when the Russian polar communications satellite Meridian 9 which has a highly elliptical orbit was seen transmitting old-style terrestrial analogue TV (ThreadReader Link). What on earth was happening?

How a Russian polar comms satellite picked up a TV station.
How a Russian polar comms satellite picked up a TV station.

The TV signal in question comes from Turkmenistan, so were some homesick Turkmenistanis in an Antarctic base being treated to a taste of their country? The truth is far more interesting than that, because the signal in question comes from a terrestrial transmitter serving domestic TV viewers in Turkmenistan.

We’ve all heard of the idea that somehow every TV show ever transmitted is somewhere out there still traveling as radio waves across space, and while perhaps we can’t fly far enough out to check for 1960s Doctor Who episodes it’s true that the horizontal transmissions from a TV tower pass out into space as the earth curves away from them.

Thus Meridian 9 passed through the beam from the Turkmenistan transmitter which happened to be on a UHF frequency that matched one of its transponders, and the result was an unexpected bit of satellite TV. We’re indebted to the work of [@dereksgc] and [Scott Tilley] for bringing us this fascinating observation. We’ve featured [Scott]’s work before, most notably when he relocated a lost NASA craft.

25 thoughts on “Satellite Snoopers Pick Up Surprising TV Broadcast

  1. How does a geostationary satellite randomly pass through a beam from a terrestrial transmitter? Isn’t the whole idea with a geostationary sat that it’s (from an Earth-based perspective) motionless and at a fixed position in the sky? If it’s in the path of the beam, wouldn’t it *always* be in the path? (Not trying to be a jerk, I just don’t understand this explanation, but it’s not really my field of expertise, either, so I might be misunderstanding.)

      1. Oh geez, I misread the article. They mentioned *most* feeds are from geostationary sats, but clearly said Meridian 9 follows a “highly elliptical orbit.”

        Thanks for setting me straight. It’s too early for this. LOL

        1. +1
          I really appreciate your asking this question with a qualifier indicating that you could be misunderstanding something, and then your willingness to confess that in fact you had simply misread a piece of information. If all commenters were like this, the comments section would be a much better place.

    1. Normal TV satellites are geostationary, but Meridian 9 is not a TV satellite and travels in a polar trajectory around the earth. Even geostationary satellites “move” a little bit, thats why large dishes have motors to track their trajectory.

  2. IIRC, the same phenomenon (radio waves keep going, out into space) was used by US intelligence to intercept Soviet leaders’ car telephone transmissions back in the 60s/70s. By placing the satellites on the horizon (relative to Moscow) they could pick up the transmissions from car to tower and tower to car.

    Read this in some book…”The Puzzle Palace”?

    1. Yeah older sats didn’t have much in the way of authentication or access control. Whatever came into the transponder at the specific frequency would get amplified possibly frequency shifted and thrown back at earth. Probably how the HBO hijacking happened long ago. Someone got a transmitter stronger than HBOs own transmitter and drowned out HBOs signal.

  3. I’m speaking under correction, but didn’t some Soviet TV satellites of the past simply use the normal terrestrial TV/Radio bands (somwhere between 60MHz and ~900MHz) for downlink so that ordinary citizens were able to pick them up without extra hardware for their TVs? Except a beam antenna, perhaps ?
    Again, I’m speaking under correction. Just heard that story in the past.

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