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Alpha Ori

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Alpha Ori

Alpha Ori is an irregular LPV that I am interested in Visually observing.  I read the article espectivion this particular variable in the Dec 2000 Variable Star of the season.  It recommended using Procyon and Aldebaran as comparison stars.  The magnitude of the two stars were given as 0.5 and 1.1 respectiveley.  However reviewing the literature I find that Procyon is list as 0.4 mag and alderbaran at 0.85.  I reported the magnitude as 0.5 as Betelgeese was approximately the same magnitude as Procyon.  After submitting the data I checked to see how close I was to other individual observations as this is a tool for me to see how well I am doing.  Most every body had the mag at 0.4.  This leads to the question am I using the wrong magnitude for the comparison stars or is my technique not as good as it should be.  How do I find the correct magnitude for these stars?

After posting I saw an error,

After posting I saw an error, sorry the second sentence I read the article on this variable...  Need to be more carfull next time.  Thanks for any information

Sebastian Otero
Sebastian Otero's picture
Betelgeuse's comp stars

Hi Robert,
you can edit your postings yourself, no need to write a new one with a correction.

About the magnitudes of Aldebaran and Procyon, indeed, they are V= 0.87 and 0.36 not 1.1 and 0.5.

Best wishes,

Belelgeuse's Comp Stars


Thanks for the informations.  I will correct my report and add the correct magnitudes to my log book.  I still need to work on my technique.  I spent a lot of time last night making the estimate.  Of course it did not help that the almost full moon was relatively near Procyon.  It was the first night in a long time that we have had anything near clear skies in Vermont.


Cheers and Clear Skies.


pox's picture
no worries

Your observation is very accurate! A difference of 0.1m for such a red, bright star as Beetlejuice is extremely impressive for a visual observation. Bright red variables are notoriously difficult to estimate, and it is not uncommon for such estimates to be wildly inaccurate - so you should be pleased with your estimate (very, very pleased!) - many leading visual observers would be happy if they got results like this every time. So, no worries!

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