The following image shows Earth and the trajectory of the ISS. A green line indicates which part of the earth can be observed from the ISS simultaneously.
What is the name of this line or this area?
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Sign up to join this communityThe following image shows Earth and the trajectory of the ISS. A green line indicates which part of the earth can be observed from the ISS simultaneously.
What is the name of this line or this area?
What is the name of this line or this area?
A term for the line that's perfectly usable for this purpose is "horizon".
The horizon, the line line separating the land from the sky, would be the green line in your image. Anything closer than the horizon will be visible to the spacecraft.
Note also that even though the area appears to have an irregular shape in your image, it's just distorted due to the map projection. It's otherwise circular.
What is the name of this line or this area?
Typically, the part of the earth's surface that a satellite can view at any moment is known as its footprint, a term frequently used for remote sensing satellites and communications satellites.
SE's answer about the horizon applies if the satellite is viewing the entire visible portion of the globe at once. As somebody pointed out in a comment, that would require a camera with an extremely wide-angle lens.
Your question is asking about ANY satellite, but then you go on to ask about the ISS. Different satellites have different orbits. A remote sensing satellite will probably have a polar orbit, where it covers the entire surface of the earth after a number of orbits.