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I understood that ISS window always faces the Earth. Wouldn't it happen if ISS was hypothetically fired in one piece around the Earth (window pointing to Earth at the start) without any further intervention (propulsion, gyro ...) ?
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Organic Marble
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DiGiorgio
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    I think you are asking "Would the ISS maintain a nadir-facing cupola attitude if attitude control systems were turned off?" Is that another way to express your question? – uhoh Dec 16 '19 at 09:05
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    I edited my question with picture and with deepest excuse for my bad drawing. So would it be object's trajectory or window would always point toward the Earth. – DiGiorgio Dec 16 '19 at 09:27
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    Does this answer your question? Why does the ISS points always the same side towards the Earth? – Ludo Dec 16 '19 at 11:47
  • In simple terms, the ISS rotates once for each revolution around the Earth. If you neglect real world effects like drag, etc, this could go on forever without 'any further intervention' once set up. Real world effects do exist though.Your sketch shows an inertially-fixed ISS, revolving without the rotation. – Organic Marble Dec 16 '19 at 11:48
  • @OrganicMarble Yes, I was wondering if my drawing will be valid for ISS with no rotation. – DiGiorgio Dec 16 '19 at 12:32
  • @Ludo Huh- I didn't find that answer. Although it's a bit beyond my moderate physics knowledge – DiGiorgio Dec 16 '19 at 12:32
  • @OrganicMarble I think you are most of the way to an answer. If put in orbit with one-rotation-per-revolution (the way it is now, cupola-pointing-nadir) it would stay like that for a short while, and if it had no rotation, it would be like a Ferris wheel, always looking in the same direction. But in addition to drag, the rotating state might also be subject to a rotational instability or might not, I don't know what the moments of inertia of the ISS are. https://youtu.be/1VPfZ_XzisU – uhoh Dec 16 '19 at 13:04
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    @uhoh It's unclear to me the level of detail that is being asked for, hence I just wrote a comment. Feel free to write an answer, as the level of detail approaches the "quadrupole moment" regime, I bow out. – Organic Marble Dec 16 '19 at 13:22
  • As an alternative (not cost-effective) approach, extend a huge hunk of mass in the desired "down" direction. Tidal lock will result :-) – Carl Witthoft Dec 16 '19 at 13:29
  • @OrganicMarble Those were both of my 2 cents, I don't have anything else. if you ever happen to run across the moments of inertia of the ISS some day please let me know; maybe we can yet skin this cat. So I've just asked Is the ISS a tennis racket? – uhoh Dec 16 '19 at 17:18
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    @uhoh there are some old ones here http://athena.ecs.csus.edu/~grandajj/ME296M/space.pdf The "latest" starts on pdf page 325. – Organic Marble Dec 16 '19 at 17:20
  • @DiGiorgio this answer might be of some relevance to your question: https://space.stackexchange.com/a/4451/33950 – Sergiy Lenzion Dec 31 '19 at 07:01

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