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: 0409-71 VW HYI 0846+58 BZ UMA No. 620 0611+15 CZ ORI 0855+18 SY CNC May 15, 2000 0640-16 HL CMA 1612-54 HP NOR 0641+28 IR GEM 1640+25 AH HER ---------------------------------------------------------------------------- 0409-71 VW HYDRI The dwarf nova type (SU UMA subclass) cataclysmic variable VW HYI is in outburst, as indicated by the observations below. Astronomers from Villanova University and the University of Washington have an upcoming observing run of VW Hyi with the Hubble Space Telescope. HST is scheduled to observe VW Hyi several times between May 20th and 25th. It is very important for scheduling purposes that our colleagues have up-to-date information with a real time light curve of the star's current behavior. A plea to our Southern Hemisphere observers - please keep a VERY close eye on VW Hyi and keep us informed of your observations continously through May 27. AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAY 10.455 13.5 SRX MAY 15.6 9.4 OB MAY 15.489 9.3 SRX ---------------------------------------------------------------------------- 0611+15 CZ ORIONIS The dwarf nova type cataclysmic variable CZ ORI is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAY 06.1597 <14.4 HSG MAY 14.281 12.3: LMK MAY 10.1431 <13.9 HSG MAY 15.281 12.1 LMK MAY 13.1493 12.3 HSG ---------------------------------------------------------------------------- 0640-16 HL CANIS MAJORIS The dwarf nova type cataclysmic variable HL CMA appears to be in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAY 08.41 <13.5 WPX MAY 13.1438 <11.8 HSG MAY 10.1389 <13.0 HSG MAY 13.394 11.8 SRX MAY 10.428 <12.5 SRX MAY 15.451 11.9 SRX ---------------------------------------------------------------------------- 0641+28 IR GEMINORUM The dwarf nova type (SU UMA subclass) cataclysmic variable IR GEM appears to be in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAY 10.1493 <14.9 HSG MAY 13.1521 <14.2 HSG MAY 11.2132 <13.6 HSG MAY 15.313 12.5 LMK MAY 12.292 <12.5 LMK ---------------------------------------------------------------------------- 0846+58 BZ URSAE MAJORIS The dwarf nova type (SU UMA subclass) cataclysmic variable BZ UMA is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAY 10.1674 <15.7 HSG MAY 13.2236 10.7: HSG MAY 11.2410 <14.8 HSG MAY 13.864 11.3 OJR MAY 12.007 <14.0 RMQ MAY 13.8958 11.0 JCN MAY 13.016 10.8 RMQ MAY 13.9097 11.6 DPV MAY 13.1660 10.5: HSG MAY 13.922 11.6 RMQ MAY 13.1778 10.6: HSG MAY 13.999 11.7 RMQ MAY 13.1903 10.6: HSG MAY 15.2118 11.6 SXN MAY 13.2007 10.7: HSG ---------------------------------------------------------------------------- 0855+18 SY CANCRI The dwarf nova type (Z CAM subclass) cataclysmic variable SY CNC appears to be in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAY 07.2465 13.6 HSG MAY 12.902 13.0 RMQ MAY 11.2208 13.1 HSG MAY 13.1590 12.0 HSG ---------------------------------------------------------------------------- 1612-54 HP NORMAE The dwarf nova type (Z CAM subclass) cataclysmic variable HP NOR is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAY 11.5764 <15.0 PEX MAY 13.8194 13.3 PEX MAY 13.401 13.6 SRX MAY 15.463 13.4 SRX ---------------------------------------------------------------------------- 1640+25 AH HERCULIS The dwarf nova type (Z CAM subclass) cataclysmic variable AH HER is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAY 12.990 14.0 RMQ MAY 13.975 13.3 RMQ MAY 13.4076 13.6 HSG MAY 14.910 12.5 SCZ MAY 13.925 13.2 OJR MAY 15.2080 12.97 CCDV ZRE MAY 13.9403 13.1 DPV MAY 15.392 12.7 LMK ---------------------------------------------------------------------------- We thank the following contributors for the data that they have provided for this News Flash: DPV - P. DUBOVSKY, SLOVAKIA RMQ - M. RESZELSKI, POLAND HSG - G. HANSON II, USA SCZ - E. SCHWEITZER, FRANCE JCN - C. JONES, ENGLAND SRX - R. STUBBINGS, AUSTRALIA LMK - M. LINNOLT, USA SXN - M. SIMONSEN, USA OB - M. OVERBEEK, SOUTH AFRICA WPX - P. WILLIAMS, NEW ZEALAND OJR - J. OSORIO, SPAIN ZRE - R. ZISSELL, USA PEX - A. PEARCE, AUSTRALIA 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! ____________________________________________________________________________