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: 2138+43 SS CYG No. 430 1801-27 V4444 SGR (N SGR 99) April 30, 1999 ---------------------------------------------------------------------------- 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 APR 28.03 11.7 KTO APR 30.0670 11.1 SJZ APR 28.3382 11.6 KMA APR 30.07 11.2 GRL APR 29.01 11.5 GRL APR 30.122 11.3 SPK APR 29.126 11.9 SPK APR 30.2996 10.7 BEB APR 29.318 11.3 MRV APR 30.2996 10.7 BEB APR 29.3194 11.5 KMA APR 30.3125 11.0 KMA APR 29.3382 11.1 SCE APR 30.3500 10.7 CSE APR 29.388 11.3 KRB APR 30.3729 10.7 BVE APR 30.0590 11.0 CMG APR 30.392 11.0 MRV As stated in AAVSO Alert Notice 257 (available thorugh the AAVSO web site), observers from Lawrence Livermore National Laboratory are scheduling multiwavelength observations of SS Cyg during this outburst. In fact, the Hubble Space Telescope (HST) is scheduled to start observing SS Cyg early next week. It is crucial that observers monitor SS Cyg closely throughout this outburst and report their observations to us daily so that we may determine the duration of the rise to maximum, maximum, and decline. ---------------------------------------------------------------------------- 1801-27 V4444 SGR (N SGR 99) Below is an update on the bright, new nova V4444 SGR (N SGR 99): APR 27.3326 7.8 SCE APR 29.105 8.8 SPK APR 27.364 7.18 ZRE APR 29.219 8.719 LIW APR 27.457 7.7 JA APR 29.291 8.9 MRV APR 27.699 7.7 JA APR 29.3174 8.8 SCE APR 27.751 7.7 JA APR 29.3540 8.94 CCDV ZRE APR 28.073 8.5 SPK APR 29.378 9.0 KRB APR 28.073 8.5 SPK APR 29.4764 9.0 SQN APR 28.152 8.09 CCDV LIW APR 29.5903 8.8 SRX APR 28.3370 9.26 CCDV ZRE APR 29.636 9.0 PEX APR 28.3431 7.6 SCE APR 30.1132 9.0 PPB APR 28.4799 8.7 SQN APR 30.3486 8.9 CSE APR 28.5764 8.6 SRX APR 30.388 9.3 MRV APR 29.026 8.6 OB APR 30.5069 9.2 SQN The scatter in these observations may be due to the fact that various observers were using different sources for comparison star magnitudes before the official AAVSO chart for this nova was issued. Please use the AAVSO chart to make further observations of this nova. The chart and the AAVSO Alert Notice on the new nova may be found on our web site: http://www.aavso.org/alert256.stm ---------------------------------------------------------------------------- We thank the following contributors for the data that they have provided for this News Flash: BEB - R. BERG, USA MRV - R. MODIC, USA BVE - E. VAN BALLEGOY, NETHERLANDS OB - M. OVERBEEK, SOUTH AFRICA CMG - G. COMELLO, NETHERLANDS PEX - A. PEARCE, AUSTRALIA CSE - D. CSERI, HUNGARY PPB - P. PECORELLI, ARGENTINA GRL - B. GRANSLO, NORWAY SCE - C. SCOVIL, USA JA - A. JONES, NEW ZEALAND SJZ - J. SPEIL, POLAND KMA - M. KOMOROUS, CANADA SPK - P. SCHMEER, GERMANY KRB - R. KING, USA SQN - L. SHAW, USA KTO - T. KINNUNEN, FINLAND SRX - R. STUBBINGS, AUSTRALIA LIW - W. LILLER, CHILE 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 Rebecca Pellock, 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! -----------------------------------------------------------------