------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 2798 2012 Jan 28 15.40UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074 INTERNET: GUY@TAHQ.DEMON.CO.UK Backup: gmh@wdcc1.bnsc.rl.ac.uk WORLD WIDE WEB http://www.theastronomer.org ------------------------------------------------------------------- POSSIBLE NEW CATACLYSMIC VARIABLE 1RXS J063214.8+253620 S. A. Korotkiy (Ka-Dar Obs.) and K. V. Sokolovsky (ASC Lebedev/SAI MSU) have reported on The Astronomer's Telegram 3893 the discovery of a bright magnitude 12.7 (unfiltered) optical transient source on 2012 January 27 at: RA 06:32:13.06 DEC +25:36:22.5 (2000). Inspection of previous images of this field revealed that the object is also present on images from 2011 Jan 24, 25, and 26 but is below the limit (typically 13.5m) on January 20 and 21. Date JD mag. 2012-01-20.740 2455947.240 >13.5 2012-01-21.701 2455948.207 >13.5 2012-01-24.759 2455951.259 13.10 +/-0.05 2012-01-25.845 2455952.346 12.81 +/-0.03 2012-01-26.833 2455953.333 12.66 +/-0.03 2012-01-27.897 2455954.397 12.61 +/-0.03 The observations were obtained with a wide-field survey camera (F=135mm f/2.0 telephoto lens equipped with ST8300M CCD) operated by Ka-Dar Observatory at the Mountain station of Kazan State University (Karachay-Cherkessia, Russia). The instrumental magnitude scale is calibrated using Tycho-2 V magnitudes. The object is associated with an ultraviolet object GALEX J063213.0+253623 (FUV=18.42 +/-0.05, NUV=17.90 +/-0.03) located 0.7" from the measured optical position. The transient is also 24" away from an unidentified X-ray source 1RXS J063214.8+253620 listed in the ROSAT All Sky Survey Faint Source Catalog. The All Sky Automated Survey (ASAS-3) lists two detections of a source at the above position: Date HJD V 2009-03-17 2454907.54944 12.82 +/-0.06 2009-03-21 2454911.53385 12.95 +/-0.06 which may be the previous outburst of this object. We conclude that the observed optical transient source is likely a previously unknown cataclysmic variable in outburst. The discovery images may be found here.: http://scan.sai.msu.ru/~kirx/ATel/1RXSJ063214/ Guy M Hurst