Re: GSC 748-1618 period

[Michael Koppelman <lolife@bitstream.net>]

Chris Lloyd and Paul Bartholdi were both kind enough to provide 
periods. The difference between them was less than 5 seconds, so I 
split the difference and used 0.7774. I gave different symbols to the 
TASS data, which is about a year old, and my data, which begins right 
at the end of December 2002 and into 2003. The new plot is here:

http://www.lolife.com/astronomy/gsc748-1618/7481618_phase_3.jpg

I want to go back and double-check the TASS data. Even if you dismiss 
the the stuff at phase 0.1 as cloudy or something, it's impossible to 
make the ascending and descending parts match up with my data. Even if 
you adjust the zeropoint, there is something funny about the difference 
between the two data sets.

 From the databases this appears to be a K-type star with B-R=1.4 
(USNO-B1.0) and B-V=0.97 (Tycho-2) and probably a Cepheid of some sort.

Michael Koppelman