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TY UMa, A Very Nice Eclipsing Binary Star

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SET's picture
TY UMa, A Very Nice Eclipsing Binary Star

Hello Everyone,


I've been out of the loop for a while, lots of changes going on in life.

I wanted to share with you a wonderful eclipsing binary star for the Spring sky for visual observers. I observered TY UMa last night and had an eclipse ranging from 11.5 to 12.1 v. This star is just off of Delta UMa and is very easy to find. If you print a "b" chart from the VSP, the bright star is Delta. Then print a "d" chart for you useful comparison stars.

TY is an W UMa type eclipser. The eclipses last 3 hours. Both the primary and the secondary eclipses range from 11.5 to 12.1, so they are both easy to observe. I use the 11.0, 11.7, and 12.4 comp stars on the chart.

Predictions for eclipses can be found on the AAVSO web site at

Submit your observations via WebObs. Good Observing!

Chris Stephan  SET

Robert Clyde Observatory

Avon Park, Florida

ZPA's picture

  Thanks for the tip! I might give this one a look. I was wondering ... are W UMa types still considered the precursors to cataclysmic variables, or somehow related to them? I remember reading that there might be a link between the two star types in the old Burnham's Celestial Handbooks, but I'm aware that much of the information in these books is outdated.

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