THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS 25 Birch Street, Cambridge, MA 02138 USA Tel. 617-354-0484 Fax 617-354-0665 http://www.aavso.org * * * AAVSO NEWS FLASH * * * Subject: 1228+15 SN 1999GQ 1216+05 SN 1999GN(update) No. 550 0547-05 CN ORI 1953+77 AB DRA December 27, 1999 0605+47 SS AUR 2138+43 SS CYG 0641+28 IR GEM 1012+41 SN 1999GI (update) -------------------------------------------------------------------------- 1228+15 SN 1999gq in NGC 4523 We have been informed by the Central Bureau of Astronomical Telegrams (IAU Circular 7337 - http://cfa-www.harvard,edu/iau/cbat.html) of the discovery of a supernova in NGC 4523 as reported by M. Papenkova and W.D. Li, University of California at Berkeley on behalf of the Lick Observatory Supernova Search (LOSS). The apparent supernova was reported on Dec. 23.6 UT at magnitude 14.5 and confirmed on Dec. 24.6 UT at magnitude 14.6. The supernova 1999gq is located at: R.A. = 12h 33m 48.32s Decl.= +15 degrees 10' 48.2" (equinox 2000.0) and is about 5" east and 46" north of the diffuse nucleus of NGC 4523 in Virgo (IAU Circ. 7337). Congratulations to the LOSS team for their discovery! ---------------------------------------------------------------------------- 0547-05 CN ORIONIS The dwarf nova type (Z CAM subclass) cataclysmic variable CN ORI is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials DEC 18.2507 <13.8 SXN DEC 27.1049 13.1 CGF DEC 19.989 14.8 PYG ---------------------------------------------------------------------------- 0605+47 SS AURIGAE The dwarf nova type cataclysmic variable SS AUR is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials DEC 19.0278 13.0 WWJ DEC 25.1170 11.56 CCDV ZRE DEC 19.2514 <13.9 SXN DEC 25.769 11.6: MUY DEC 19.424 15.2 MRV DEC 25.97 11.5 DGP DEC 19.866 14.8 PYG DEC 26.024 11.6 MRV DEC 20.801 <13.2 MUY DEC 26.841 11.6 OJR DEC 21.827 <12.5 MUY DEC 27.0056 12.4 BRJ DEC 23.767 11.4 MUY DEC 27.0194 12.2 CGF ---------------------------------------------------------------------------- 0641+28 IR GEMINORUM The dwarf nova type (SU UMA subclass) cataclysmic variable IR GEM is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials DEC 18.2646 <14.2 SXN DEC 26.257 13.2 CCDV BCY DEC 19.998 <14.7 PYG DEC 26.265 13.2 CCDV BCY DEC 25.2490 16.50 CCDV ZRE DEC 26.275 13.1: CCDV BCY DEC 26.226 13.3 CCDV BCY DEC 26.285 13.1: CCDV BCY DEC 26.240 13.2 CCDV BCY DEC 26.293 13.0: CCDV BCY DEC 26.249 13.2 CCDV BCY DEC 26.302 13.1: CCDV BCY ---------------------------------------------------------------------------- 1012+41 SN 1999GI We have received the following observations of the supernova SN 1999GI; since the release of News Flash No. 547: AAVSO Observer UT Mag. Initials DEC 26.4097 14.4 CCDV RR ---------------------------------------------------------------------------- 1216+05 SN 1999GN We have received the following observations of the supernova SN 1999GN; since the release of News Flash No. 547: AAVSO Observer UT Mag. Initials DEC 24.5729 15.0 CCDV RR ---------------------------------------------------------------------------- 1953+77 AB DRACONIS The dwarf nova type (Z CAM subclass) cataclysmic variable AB DRA is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials DEC 25.0 <14.0 CGF DEC 25.97 12.9 DGP DEC 25.738 13.0 MUY DEC 26.9778 12.7 BRJ DEC 25.7813 13.4 JCN DEC 27.0042 13.1 CGF ---------------------------------------------------------------------------- 2138+43 SS CYGNI The dwarf nova type (SS CYG subclass prototype) cataclysmic variable SS CYG is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials DEC 19.0465 11.3 SXN DEC 22.7510 11.6 SJZ DEC 19.76 11.8 VET DEC 23.760 10.6 MUY DEC 19.810 11.9 PYG DEC 24.9743 10.3 CGF DEC 19.971 11.7 MRV DEC 25.735 10.0 MUY DEC 20.0181 11.9 BVE DEC 25.97 9.6 DGP DEC 20.73 11.9 VET DEC 26.020 9.8 MRV DEC 20.779 11.4 MUY DEC 26.0965 10.0 AAP DEC 21.0000 11.6 BVE DEC 26.833 9.3 OJR DEC 21.024 11.5 MRV DEC 26.9764 9.5 BRJ DEC 21.7104 11.6 FSE DEC 26.9799 9.4 SET DEC 21.807 11.8 MUY DEC 26.9861 9.3 CGF DEC 22.1111 11.2 RR DEC 26.9986 9.2 BVE ---------------------------------------------------------------------------- We thank the following contributors for the data that they have provided for this News Flash: AAP - A. ABBOTT, CANADA MUY - E. MUYLLAERT, BELGIUM BCY - C. BRYJA, USA OJR - J. OSORIO, SPAIN BRJ - J. BORTLE, USA PYG - G. POYNER, ENGLAND BVE - E. VAN BALLEGOY, NETHERLANDS RR - R. ROYER, USA CGF - G. CHAPLE JR., USA SET - C. STEPHAN, USA DGP - G. DYCK, USA SJZ - J. SPEIL, POLAND FSE - S. FOGLIA, ITALY SXN - M. SIMONSEN, USA JCN - C. JONES, ENGLAND VET - M. VERDENET, FRANCE MRV - R. MODIC, USA WWJ - W. WILSON, ENGLAND ZRE - R. ZISSELL, USA Please monitor these and other variable stars closely and phone-in, fax, or e-mail your observations to the AAVSO. Good observing! Janet A. Mattei, Director Gamze Menali, Technical Assistant ____________________________________________________________________________ Symbols may include: < = fainter than magnitude given (variable not seen) : = uncertain CCDV = Charge-coupled device with (V) filter If you would like to contribute to AAVSO NEWS FLASH, please send observations of unusual variable star activity to: observations@aavso.org Those who wish to subscribe (free of charge) or unsubscribe to NEWS FLASH may do so by visiting the following web page: http://www.aavso.org If you would like data from the AAVSO International Database for research purposes, please send your request to: Janet Mattei, AAVSO Director, at aavso@aavso.org An archive of past issues of the News Flash is available at the following web page: http://www.aavso.org/newsflash/ We look forward to including your observations in future editions of AAVSO NEWS FLASH! ____________________________________________________________________________