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Mira and its neighbors

PKV's picture
PKV
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Joined: 2010-07-26

As Mira (OMI CET) rises in the east and places herself in the evening sky, you may wish to observe two lesser observered variables.  In the parallelogram-shaped asterism 2.5 degrees north of Mira, lie R and RS CET.  R CET is a Mira which varies from 7.2 to 14 V in 166.24 days and is now fading at 9.1 Vis.  RS CET is a questionable SR which varies from 7.9 to 8.6 V with an undetermined period. 

In looking at the ASAS data for RS CET however, this SR classification seems doubtful, with most of the observations clustering around 8.4 V.  Check out:  http://www.astrouw.edu.pl/cgi-asas/asas_variable/022800+0013.3,asas3,0,0,500,0,0).  Is RS CET constant?  It seems so, but their are some outlier observations.  RS CET is also listed a G star, not M, C or S which are common for other pulsators.  Any comments or ideas?  RS CET is problematic at best.

If you observe Mira, give a R CET a look.  It is easy to find and this under-observed Mira is worthy of your attention.

Kevin Paxson - PKV

RS Cet is constant
Sebastian Otero's picture
Sebastian Otero
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Joined: 2010-09-19

Hi, Kevin,

RS Cet is not more a variable star in VSX. That's the good thing about VSX, you can revise it with the available data in real time.
Thanks for calling the attention to this star. It is constant everywhere we look.

Cheers,
Sebastian

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Sebastian Otero
VSX Team
American Association of Variable Star Observers

RS CET is constant
PKV's picture
PKV
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Joined: 2010-07-26

Sebastian,

Thanks for the VSX update today of RS CET.  Now another variable is now off my list.  It makes one wonder about all those RS CET observations over the last 15 to 20 years showing variation.  Oh well.  Great job Sebastian!!!

Kevin - PKV 

Observing constant stars
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Sebastian Otero
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Joined: 2010-09-19

Don't worry, I was one of the visual observers of CK Ori and T CMa and I used to see some small variations on them when they are constant... We need to know our limitations. One of the most important one is bias. When we are told that a star varies, we are probably going to see it vary.
I think that being critical of our own measures is as important as trying to use the best techniques possible to increase our accuracy.
 

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