> Are you telling me you don't know what the term "frame of reference" means
… I know what a frame of reference is.
> or how to establish one?
That's the entire question, here. For a given star system, how do you establish a frame of reference to then decide whether the system as a CW or CCW spin, without the determination being arbitrary, since we're asking to learn something about nature here.
> You can pick any 3 stars and say "For the purposes of the next 5 minutes, let's call this star A and this star B and this star C. A is the north pole, B is the south pole, C is 12 o-clock or 0 degrees, and degrees count up clockwise when looking from north to south."
We were trying to establish the spin of a star system. Short of it being a binary star system, there's one star.
We can't really consider multiple star systems simultaneously, as it wouldn't make any sense. Say you pick a star at random, A; you arbitrarily designate one of the two poles of the star as "north", and "up" as a vector straight up from the star's "north" pole. First, the CCW/CW rotation of star system A hasn't been decided by any fundamental law of the universe, it's been decided by our choice alone. Had we chosen the other pole to designate as north, then the rotation is reversed.
If we go to a second system, B, and maintain our definition of "up" as "up in the A system" … that makes no sense. This system could be edge-on the the up vector from A. For B's rotation, we need a vector perpendicular to the plane of system B.
(Whether a system is CCW or CW is going to be about the "up" vector, but the "up" vector for a system has to be from the system's center, and then perpendicular to the plane of rotation.)
… I know what a frame of reference is.
> or how to establish one?
That's the entire question, here. For a given star system, how do you establish a frame of reference to then decide whether the system as a CW or CCW spin, without the determination being arbitrary, since we're asking to learn something about nature here.
> You can pick any 3 stars and say "For the purposes of the next 5 minutes, let's call this star A and this star B and this star C. A is the north pole, B is the south pole, C is 12 o-clock or 0 degrees, and degrees count up clockwise when looking from north to south."
We were trying to establish the spin of a star system. Short of it being a binary star system, there's one star.
We can't really consider multiple star systems simultaneously, as it wouldn't make any sense. Say you pick a star at random, A; you arbitrarily designate one of the two poles of the star as "north", and "up" as a vector straight up from the star's "north" pole. First, the CCW/CW rotation of star system A hasn't been decided by any fundamental law of the universe, it's been decided by our choice alone. Had we chosen the other pole to designate as north, then the rotation is reversed.
If we go to a second system, B, and maintain our definition of "up" as "up in the A system" … that makes no sense. This system could be edge-on the the up vector from A. For B's rotation, we need a vector perpendicular to the plane of system B.
(Whether a system is CCW or CW is going to be about the "up" vector, but the "up" vector for a system has to be from the system's center, and then perpendicular to the plane of rotation.)