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Explaining Constellations

the post:

If the Milky Way galaxy is constantly rotating are all the constellation's still in the exact same place as they were during the last say 50 thousand years and if so does this mean almost every star is travelling in a constant perfect sync with each other?

my comment:

I posted on October 29 a study of IC342 found an electric current in each spiral arms generates a magnetic field that can bring stucture to the arms. The Milky Way has a few billion stars in rotation in the disk due to the galactic magnetic field but there is a mix of electromagnetic forces at play to exhibit some order in the chaos.

the response:

so most of the stars in the galaxy travel in sync to one another over thousands of years and the constellation's are in their same place since the last precession?

my response:

Unfortunately this is not so simple.
Clusters are usually checked whether the stars have the same metallicity implying they have a common age and are probably remaining together.
Many constellations are populated with a variety of stars so they are assumed to be in that arrangement by their random motions. If any are nearly identical then they could be assumed to be related and could be moving together. Constellations typically cover a large volume so I expect most will change over time.

the response:

so why are the constellation's still in the same place as around 26 thousand years ago or aren't they?
my response:

The Sun's orbit is assumed to take over 200 million years for one lap.
These changes  take a very long time. My first response was the pessimist view. The optimist view is we will see these constellations for many years.

my comment to another comment in the stream:

About egos:
It was a revelation that external galaxies were first revealed in the 1920s.
Much has been learned in just 100 years and I am in this group to learn too. There are so many pieces in this puzzle. Those claiming to know it all are delusional.
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