Whilst watching NASA TV over the years, I've often seen the map on the wall of Mission Control:

  Main Screen in the ISS Mission Control Center

  "Main Screen in the ISS Mission Control Center", by AGeekMom, CC BY 2.0

In this image, as well as the orbital track of the ISS, we see a number of other regions:

  • A light blue line enclosing North and South America, and much of the Pacific and Atlantic Oceans
  • A green line enclosing Europe, Africa, parts of Asia, parts of South America, the Atlantic Ocean and possibly the South Pole
  • A yellow line enclosing Asia, Australia and much of the Pacific
  • Various smaller yellow lines enclosing labelled areas, mostly over Russia
  • A smaller area in the southern Atlantic labelled SAA
  • A circle around the ISS itself.

What exactly do these represent?

  • $\begingroup$ I wondered whether they were areas where radio coverage is better, eg where the TV pictures can be sent over the KU band, but watching closely this doesn't seem to be the case? $\endgroup$ Commented Dec 30, 2015 at 16:08
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    $\begingroup$ SAA = en.wikipedia.org/wiki/South_Atlantic_Anomaly $\endgroup$
    – Hobbes
    Commented Dec 30, 2015 at 16:10
  • $\begingroup$ Considering soyuz can only be reached when flying over russia, this could be the case for the small yellow area over it. $\endgroup$
    – Antzi
    Commented Dec 30, 2015 at 16:10

1 Answer 1

  • The three big areas (light blue, green, yellow) outside of what looks like the enclosed area on the equirectangular projection are geosynchronous satellite TDRSS (Tracking and Data Relay Satellite System) coverage areas for S Band communications *,
  • Smaller yellow areas over Russia are ground-based tracking and data relay stations,
  • The white area in South Atlantic is the South Atlantic Anomaly (SAA)
  • The white circle around the ISS is area of direct line of sight to the station from the ground,
  • Thin line between a dimmed and illuminated region of the Earth is the solar terminator
  • White square brackets over ISS ground track are indications of orbital sunset and sunrise (thanks Ben Honey!)

* Coverage areas of each of the three TDRSS satellites (also shown color-coded on the map) are bigger than half the Earth's surface on the map because of adjustment to ISS orbital altitude. So the light blue line enclosing is the no cover zone that's antipodal to T275W that is shown just South of Sri Lanka and below the ISS on the image. I realize that this might look odd on a equirectangular projection map, but in a sense both sides of these lines are circles on a globe of the Earth. The bigger area side is inclusion area where communications are possible with that satellite before the station sets behind the Earth from satellites vantage point, the smaller one (I guess it could be deemed the enclosed one on the projection) is the exclusion zone where coverage has to be provided by the other two TDRSS satellites spread roughly 120° around the globe in a small inclination geosynchronous orbit, or ground based stations where available and in direct line of sight with the station.

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    $\begingroup$ Just seen your * - would it be more accurate to say that the 3 large areas are therefore TDRSS lack of coverage? $\endgroup$ Commented Dec 30, 2015 at 19:34
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    $\begingroup$ @JamesThorpe Neah, that just depends on how you look at it. Both are circular areas on a globe and the light blue line encloses both of them, they just look a bit odd on the equirectangular projection (everything at high latitudes does really, e.g. Australia is over 3 times bigger than Greenland yet it looks about the same size on the map). It just had to be said, but positions of TDRSS satellites and color-coding make that clear enough IMHO. $\endgroup$
    – TildalWave
    Commented Dec 30, 2015 at 19:49
  • $\begingroup$ Yeah fair enough :) $\endgroup$ Commented Dec 30, 2015 at 19:51
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    $\begingroup$ For a video version of explaining the Main mission control screen... https://www.youtube.com/watch?v=6zFAme3SQAo which also includes an explanation of the beta angle and some other details. $\endgroup$ Commented Apr 25, 2020 at 14:49
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    $\begingroup$ And this link https://www.wral.com/a-view-of-the-equinox-from-mission-control/19020228/ further explains many of the acronyms shown on the main mission control map. $\endgroup$ Commented Apr 25, 2020 at 15:18

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