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?
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.
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.)
I believe Meridian 9 is not a geostationary satellite, as the article states it has a highly elliptical orbit. I assume they were talking about digital TV satellites in general, which isn’t what Meridian 9 is.
It is a Molniya orbit, pretty interesting solution to provide satellite to northern regions.
Or southern regions if that’s where the perigee of the orbit is. The catch-all phrase is “high-latitudes”, to mean either very northerly or southerly latitudes.
Meridian 9 doesn’t appear to be a geostationary satellite. It is in a polar orbit.
https://www.n2yo.com/satellite/?s=45254
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
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.
I need to finish reading this, but, in theory, we should be able to abuse these for satellite “cb” radio service here in Canada.
Thanks, Jace. I came back to this page expecting to see 30 more people smacking me down for my mistake, but I got to see this instead!
Meridian satellites are not geostationary. They are on a highly elliptical orbit.
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.
Think the text reads as: USUALLY it’s from a geostationary satellite, but Meridian 9 which received this signal is not one of those.
Yup, got it. Several others beat you to correcting me.
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”?
Very cool relay. Satellite doesn’t care what its relaying, just receive and send…. It happens to fall on the right frequency. Sounds like the pirate Brazilian truckers using cb radio over navy satellite.. perhaps a little less pirate tho. https://www.wired.com/2009/04/fleetcom/
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.
Meanwhile on a couch far far away… ET and a few of his mates begin fighting over the remote.
Maybe they’re watching from the star Vega.
Wanna go for a ride?
If we leave now we might get there before the release of Nosferatu!
You mean like this?
https://cdn3.whatculture.com/images/2018/09/e06d4b4d780f5996-600×338.png
Interesting, but wouldn’t this have happened many times before?
Likely… only notice if you are listening or trying to decode tv stations on that frequency at a location the satellite is point back to.
You should have a look at Scott Tilley’s blog, especially the most recent post. According to that the Meridian satellites are part of a communications network also used by the Russian nuclear forces. Interestingly there seems to be a bit of problem with it beyond just randomly multipliying SECAM signals. You can find it here: https://skyriddles.wordpress.com/2022/03/10/you-can-call-me-dmitry-meyer/#more-1118
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.