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Date: Mon, 3 Mar 2003 18:16:25 +0300 (MSK) From: "Nikolai N. Samus" <samus@sai.msu.ru> Dear colleagues, We have looked into the problem of suggested identifications for V1485 Cyg attentively. In IBVS No. 4675 (1999), B. Skiff published for these star accurate coordinates (19:38:08.1 +29deg40'43", 2000) and identifications with CSV 4759 (this CVS object is just the previous name of V1485 Cyg) and NSV 12238 (considered a different star by the GCVS team at that time). In 2000, V.P. Goranskij, a GCVS team member, measured an accurate position for V1485 Cyg, found to be 19:38:08.660 +29deg40'53".70 (2000.0); it is this position (somewhat rounded) that is currently returned by the Query Form at the GCVS web site. He thus considered Skiff's findings wrong and did not analyze the suggested NSV identification. Goranskij's star is beyond doubt IRAS PSC 19361+2933. B. Skiff now suggests still another NSV identification for V1485 Cyg, with NSV 12235 (actually there is no conflict in variability type; ea in the NSV catalog is in the "Spectral type" column and stands for Halpha in emission). Our assessment of the finding chart for NSV 12235 in Vatican Publ. 1, No. 5, 181 (1974) is somewhat different from that suggested by Brian Skiff. Namely, TAKEN AT FACE VALUE, it leads to the comparison star "f" for V1485 Cyg in: A.A. Wachmann, Bergedorf Abhandlungen 6, Nr. 4, 289 (1966). HOWEVER, the cited Vatican paper gives for VES No. 28 (NSV 12235) B-V=2.73, and the comparison star "f" is neutrally colored according to modern data (including 2MASS). We think that the Vatican chart, reproduced from POSS blue prints, did not show the red star, and a faint neighbor was erroneously marked. The position in the Vatican paper is in good agreement with OUR position for V1485 Cyg. The chart for NSV 12238 (zone +29deg, star No. 104, B. Westerlund, Astrophys. J. Suppl., No. 37, 73, 1959) FORMALLY also leads to a neutral-color faint star (another one). However, Westerlund calls it an M9 star, and the ONLY star sufficiently red and bright in this sky region is V1485 Cyg. We think that Westerlund's chart was corrected by hand, with faint stars added, and thus it shows the position of the star not accurately enough. On March 3, Chris Lloyd distributed an e-mail message claiming that the position in SIMBAD was correct (which we think is not the case; SIMBAD reproduces the position from IBVS No. 4675). We don't quite understand Lloyd's remark about the Catalogues of Wolf - Rayet stars, these catalogues contain, to the best of our knowledge, no objects at the position of V1485 Cyg, and this variable is not a Wolf - Rayet star. Summarizing: we now decide to identify, for GCVS purposes, V1485 Cyg, NSV 12235, and NSV 12238. The only star revealing a very red color is Goranskij's candidate for V1485 Cyg. Its GSC 2.2 position (19:38:08.664 +29deg40'53".71, 2000.0) is in EXCELLENT agreement with Goranskij's astrometry. Best regards Elena Kazarovets Nikolai Samus On Sun, 2 Mar 2003, Brian Skiff wrote: > As best I can tell, comparing the finder charts for these two stars > appearing in 1906AN....172..349W and in 1974VatOP...1..181C, they are > identical, despite their conflicting variability types. The star is > a red IRAS source, so the semiregular type is certain (the NSV star is > suspected of being an Algol-type eclipser). > > \Brian >
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