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For obvious reasons the ISS cannot get cable TV. Can the ISS get the new digital air TV or satellite TV using an issued dish and receiver like a house? How would that be done compared to how it is normally received?

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  • $\begingroup$ A big issue with data exchange from the station is always security. IIRC They used to have a setup where they could browse the internet by way of a camera in Huston pointed at a monitor and a keyboard and mouse wired to be strictly one-directional. I don't know if the data rate and fidelity of something like that would make for a good viewing experience. $\endgroup$ – Rikki-Tikki-Tavi Oct 2 '18 at 5:21
  • $\begingroup$ Could we launch a satellite in a polar orbit that matches the ISS's period to bring them cable on demand? $\endgroup$ – Magic Octopus Urn Oct 3 '18 at 6:10
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More or less.

While the ISS is below the satellites use for TV transmissions, it is passing by so fast that the coverage will be highly intermittent, meaning that you would be able to watch a channel for only a couple of minutes, have black outs over the oceans, and repeat.

Other notable differences would be:

  • Normal satellites receiver are "fixed": The dishes don't move. As the ISS is travelling, the antenna will need to move to track the satellites.

  • The ISS is moving... And it's moving fast! There will be a significant doppler effect; and the receiver will need to account for that (broader spectrum antenna, and shifting the frequency dynamically).

  • The licensing might be a bit complicated; it's unclear whether space is included in the bundle.

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    $\begingroup$ The licensing might be a bit complicated; it's unclear whether space is included in the bundle - If the content they can watch depends on which country they're hovering, they're going to have a hell of a time. $\endgroup$ – Baptiste Candellier Oct 2 '18 at 8:35
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    $\begingroup$ @Dan, The orbital speed of the ISS is approximately ten times the speed of a bullet shot from a high-powered hunting rifle. I'm not sure what your outlook is, but "hover" just doesn't seem to represent that kind of motion to me. $\endgroup$ – user27176 Oct 2 '18 at 15:22
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    $\begingroup$ @besmirched It hovers in the same way that flying works in Hitchhiker's Guide: by falling and not hitting the ground :-) $\endgroup$ – Aaron F Oct 2 '18 at 15:52
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    $\begingroup$ @AaronF, Dang! No wonder so few people mastered the art. When they said, "throw yourself at the ground and miss," they never said how hard you had to throw yourself. $\endgroup$ – user27176 Oct 2 '18 at 17:11
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    $\begingroup$ The ISS does get streaming services via the Ku-Band TDRSS link. It doesn't have any antennas to point to any other GEO satellites. $\endgroup$ – Tristan Oct 3 '18 at 15:22
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@Antzi's answer is right, but I'll add some context as a supplement.

  • While Doppler (mentioned there) might or might not be an issue for an off-the-shelf commercial satellite TV box (I don't know) it could probably be fixed with a mod that NASA could easily manage.

  • Several answers to Do astronauts get Netflix on ISS? indicate that there is access to "new stuff to watch" beyond what content astronauts may bring themselves. This also implies access to other internet content as well.

The real problems with satellite TV at least:

NASA's TDRS satellites are at the same geosynchronous altitude as "TV satellites", and in fact are more "wobbly" (higher inclination) and yet are to the go-to solution for data and comms for the ISS.

  1. "TV satellites" in GEO would be regularly eclipsed by the Earth. With a ~90 minute orbit you'd loose line-of-sight communications at irritating moments during 1 hour and many half-hour "shows". For TDRS you just need to slew the dish to the next position since they are clustered in groups distributed around the Earth.

  2. You'll need some more of the expensive articulated dish antennas to constantly track the "TV satellites" as the ISS orbits, as well as another place to put them, and more power and cables to connect them to. See this excellent answer to the question Do antennae on the ISS have to constantly move to maintain data links? There's even a video!

edit: In the future a flat phased array antenna might do the trick nicely (for TV reception) and be cheaper as well as far faster in the "slewing". Still, it's some serious work to connect them.

  1. Selecting the right TV viewing package (as pointed out in @Antzi's answer) might be a substantial challenge even for NASA. It sounds like a question that the US House of Representatives could spend months investigating.
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Can the ISS get the new digital air TV or satellite TV...

As far as Digital over the air TV is concerned, it's the same as old-fashioned TV in that both are transmitted from terrestrial transmitters. Different signals (digital vs analog) and different frequencies, but that's not the point here.

Terrestrial TV is intended to serve a local area around the transmitter, typically 10s of miles, with perhaps 50 to 100 miles possible between a tall transmitter (100s of feet) and a tall "fringe" receiving antenna (maybe 50 ft). Beyond that, you are over the horizon (VHF/UHF is essentially line-of-sight) and signal strength gets pretty weak before you reach the horizon.

The ISS orbits about 400 km above MSL, so line-of-sight is much further - perhaps 1000 miles, but at over 17,000 mph, the ISS would go in and out of a station's line of sight in just a few minutes. Also, TV transmission antennas are designed to emit the strongest signals horizontally to the horizon, not upward into space. That means the ISS will never get very good reception even when in line-of-sight - it will either be very far away or out of the region of strongest signal.

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It apparently is possible to watch TV on the ISS. Here is a picture of three astronauts aboard the ISS watching a live transmission of a football game from the FIFA world cup in 2014:

Astronauts watching football

You might notice that they are watching it on a notebook, so it appears to be an Internet live stream, not a satellite broadcast.

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