[vsnet-chat 5688] Re: CK Ori and W Ori tonight

[DWest61506@aol.com]

Sebastian wrote:

<And for Pat, I also confirm his observation of W Ori still at
  5.8. It is
  very quiet now.>

I downloaded all of the W Ori observations from VSNET and performed some simple analysis to try to better understand the visual observations of this giant carbon star.  The observations I looked at ran from January 1946 to December 2001.  A plot of the observations revealed multiperiodic behavior.  I used various moving averages to filter the observations.  Plotting the observations I measured part of the time between peaks with the following results: 140, 670, 682, 391, 407, 408, 363, 413, 973, 671, 469, 729, 399, and 617 days.  The GCVS gives a period of 212 days.  It could be argued that most of the times between maxima correspond roughly to a multiple of the 212 day GCVS period.  The average for the over 7000 observations was 6.51 and the standard deviation was 0.37 magnitude.  Taking three standard deviations either side of the mean gives a visual range of 5.40 to 7.62.  W Ori is definitely near a maximum.

Regards,
Doug West
http://hometown.aol.com/dwest61506/index.html

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