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02:26
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A: Is it possible to achieve a stable "lunarstationary" orbit around the moon?

zephyrFirst off, such an orbit wouldn't be a geostationary orbit since geo- refers to the Earth. A more appropriate name would be lunarstationary or selenostationary. I'm not sure if there is an officially accepted term since you rarely hear people talk about such an orbit. You can calculate the orbit...

I suspect that, if and when space travel becomes common enough for average Joe to care about surface-stationary orbits around bodies other then Earth, they'll probably be called geostationary by all but the most pedantic. Being pedantic myself, I propose using "surface-stationary" instead as a generic term.
@Walt or how about just "stationary orbit".
If the Earth wouldn't disturb, the masons wouldn't interfere with the stationary orbit, would it?
@Džuris I wouldn't expect so, but I can't be sure without more research. My suspicion is that if a body was orbiting at the selenostationary orbit, it'd be high enough that the mascons wouldn't have a noticeable effect.
Why not just synchronous orbit?
02:26
@LorenPechtel that's a slightly different category. A stationary orbit is synchronous, but a synchronous orbit can be non-stationary. All you need for a synchronous orbit is the right period (in a non-retrograde direction), but you can wobble around as much as you like during each orbit.
The Earth is in a selenostationary orbit. That's what it means for the Moon to be tidally locked to the Earth.
@MikeScott: No, not really.
@Walt I really hope people would notice that geo- really just refers to Earth. I would go nuts if people talked about geostationary orbits around mars. It has nothing to do with being pendantic, but using the proper language/terms. Being wrong is wrong, no matter how many people mis-use it (1+1 is not three, no matter how many people might believe otherwise).
@Polygnome Is there a generic term that would refer to any object around which an orbit might be attempted?
@Barmar If there is, I've never heard it and can't find a reference to one. I think your best bet is to just leave off the prefix qualifier and call it a stationary orbit. Unlike terms like apoapsis and periapsis, there's no general prefix that I know of that you can prepend to stationary to make it mean a general case.
02:26
@zephyr That lack might excuse people who misuse "geo-" for this. This type of generalization is common -- many people informally refer to other "solar systems", rather than the more technically correct "stellar systems".
@Polygnome It's not so different from saying "Kleenex" to refer to all facial tissue, or "Coke" to refer to carbonated beverages, or "Thermos" to refer to an insulated container. Would you have a problem with people referring to Martian terrain? What about using geothermal energy on Mars? Solar energy from a star other than ours? In most geo- and terra- root words, there's a strong argument to be made that those roots don't mean "Earth, the 3rd planet from the star Sol" but instead something more like "earth, the ground".
@Barmar A stellar system is a system of stars, such as a galaxy or star cluster, while a solar system is the system of bodies associated with the sun or a star and travelling with it.
@Barmar A solar system does not exist. The solar system is the system of planets around or Sun, Sol (hence, Solar system). Systems around other stars are simply star systems, like TRAPPIST-1.
@Barmar "surface-stationary" will be understood. Instead of geo-, there are well established prefixes for a lot of other bodies as well.
@Polygnome Not to beat a dead terminology horse, but standard astronomical terminology refers to star or stellar systems as a group of stars. A better term for a solar system would be a planetary system. See forums.robertsspaceindustries.com/discussion/227656/…
@Timm I don't think there's any "standard" terminology given that no official organization like the IAU has set a standard concerning this. That being said, I've more commonly heard the usage implied by Polygnome, i.e., that we reside in the solar system while other star systems, which may or may not have planets, are referred to as stellar systems. It is true though that stellar system can more generally refer to a collection of stars, but often there are specific terms for specific types of collections, e.g., globular clusters.
02:26
@zephyr I didn't mean to get into an off-topic discussion about terms. The OP asked a concrete question, and you (sorry Philipp) provided a terse and insightful answer. So be it.
@Polygnome Language is not like math. The meaning of terms often changes with the passage of time, simply because people use a term differently and that usage spreads. Also, our sun doesn't appear to have a commonly accepted proper name: earthsky.org/space/what-is-the-suns-name.
@jpmc26 The article just says that media isn#t able or willing to follow IAU standards. language can be precise if you want it to be. Most people just don't bother.
@Polygnome It can only be that precise if everyone agrees to make it that precise. The general populace certainly does not. The only reason it focuses on the media as a "non-IAU" organization is because it isn't even possible to coral the rest of the populace enough to even make a statement about them.
Blah. I hate typos. *corral (Sorry to bug anyone with this message.)

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