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RGN's picture
Joined: 2010-09-11

It appears that Z UMI is undergoing one of its deepest minima (below 18th mag). I have seen that there are a few observers that reguraly follows this RCB star. Since I have leraned that the minima are particularly important to determine the physical properties of RCB stars I wonder whether the AAVSO has given notice to professional astronomers and if there are some of them that are currently taking the spectrum of Z  UMI.


These deep minima are indeed
wel's picture
Joined: 2010-07-26

These deep minima are indeed scientifically valuable - they allow a close examination of the environment of the R CrB variable when adaptive optics are used.



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