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wnvalliant t1_it7fkwm wrote

Reply to comment by Aceticon in China looked at putting a monitoring satellite in retrograde geostationary orbit via the moon by OkOrdinary5299

I understand what you mean about drifting above or below the ring but it would still be going pro-grade with respect to the spin of the earth.

Definitely the paper is saying this proposed satellite would be retro-grade. That would reduce visit times for spying on other satellites and other less nice things.

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Aceticon t1_it7nri9 wrote

I think I used the wrong terminology.

By "higher" I meant with a higher Apoapsis and Periapsis, so an orbit further out than GEO.

It's not possible to have an orbit fully above or below "the ring" (I presume you mean the orbital plane) - the best you can do is an orbit which is part of the time above and part of the time below, i.e. with an orbital tilt.

This makes sense if you think of the methaphor were you are rotating a bucket full of water at the end of a rope: if you try and make it go higher in relation to the hand which holds the rope you'll find it just goes down at the other end of the circle, making inclined circle, half the time above that point and half below.

The very same effects that keep an object in orbit by pulling it towards the Earth also pull it down when higher and up when lower, effectivelly forcing the orbit to be in a mathematical plane that includes the Earth, though a plane that can be different than the normal orbital plane.

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wnvalliant t1_itag82b wrote

Only thing I was trying to say to you was that the article from spacenews about the chinese paper was describing an orbit different than you were talking about.

I understood you about the drifting around the main geo belt satelites thing. "the ring" is me using bad terminology for the ring of satellites orbiting the earth, circular, at whatever it is, 42km or whatnot, over the equator, sorry to confuse. Note that those are pro-grade (spinning with the rotation of the earth) and that the Chinese article was talking about going the opposite direction (spining against the rotation of the earth).

It is possible to orbit the earth any way you want as long as you are not too high or low from the earth to get influenced by the atmosphere or the moon or whatever.

You sound like you are into the subject and did great describing things by the way! Sorry about the miscommunication Aceticon...

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