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> So, what "FORMERLY TY SGE" actually refers to is an identification error in the former AAVSO charts?< Precisely. The current AAVSO charts for RZ Sge were revised to indicate the correct position of TY Sge in March this year. Observers using previous versions of the AAVSO chart were making estimates of this other variable, and TY was being used as a comp star! New charts with Henden photometry and the positions and IDs of all these stars will be published in October. >Am I correct to interpret that this doesn't imply that the true identification of TY Sge is recently recovered (as in GM Sgr and V4641 Sgr)?< Correct. AAVSO charts are now in agreement with the GCVS. TY SGE = GSC 1621:53 based on the original charts in AN 170, 361, 1906. N. Samus also confirmed Schmidt's finderchart to match that of M. Wolf and G.Wolf's from AN 1906. >[But if this is the case, I wonder why the AAVSO don't use a more specific (at least better...) name such as SGETYVAR rather than SGEVAR.]< You will get no argument from me that the system for naming secondary variables or suspected variables on AAVSO charts is both archaic and confusing. Frankly, I just didn't know what else to call it in my report. That is why I made a note in the comments section. Remember, my observation is based on a chart that is still unpublished, so HQ has not assigned an identity or HD to this star to distinguish it from the real TY Sge. Dan Taylor is preparing a report for AAVSO HQ to clarify the situation and assign the proper observations to the correct light curves in the database, based on the vintage of chart used to report the observations. Eventually, we may get a more definitive answer as to what to call this other variable in our AAVSO reports. I have no preference and will call it Herman if you like :-) >We have a number of "TY Sge" observations reported to the VSNET. The observers are: Poyner, Vanmunster, Diepvens, Taylor, Commelo and Simonsen. Should all these observation be renamed to GSC2.2N0211313705? Comments from other observers are also welcomed.< Each of these observers will need to clarify the ID of the star they have been reporting as TY Sge. Interestingly, the star previously mis-identified as TY Sge on AAVSO charts was classified as a UG? from its spectrum. Henden's measurements of this star indicate it is blue(B-V=0.634+/-0.022). It sems to exhibit periods of inactivity and then alternately gets active. Dan has reported seeing flickering on several occassions he has observed the star. "Herman" may prove to be more interesting than TY Sge. Mike Simonsen
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