Why are the 'Fixed Stars' so FIXED?

On 12 Mar, 22:11, HW@....(Henri Wilson) wrote:

....
Have you seen this?http://mb-soft.com/public2/cepheid.html

He cites "Duncan" without further information. A bit
of a browse suggests it is a curve from 1921 !

This is a more recent curve from an amateur:

http://www.student.oulu.fi/~ktikkane/AST/RTAUR.html

There is far more detail in that which shows how far
the capabilities have come, and I suspect you'll get
even better data if you do some serious searching.
Note the amount of detail in the variations.

George