THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS 25 Birch Street, Cambridge, MA 02138 USA Tel. 617-354-0484 Fax 617-354-0665 INTERNET: aavso@aavso.org * * * AAVSO NEWS FLASH * * * Subject: Z Cha, BL Lac, TZ Per, VZ Pyx, UZ Ser No. 270 March 11, 1998 ________________________________________________________________________________ Z CHAMAELEONIS The eclipsing dwarf nova type (SU UMa subclass) cataclysmic variable Z Cha appears to be in outburst, as indicated by the following observations: AAVSO Observer UT Mag. Initials MAR 09.4903 <14.0 SRX MAR 11.4403 12.8 SRX MAR 11.4597 <14.0 SRX MAR 11.4632 12.8 SRX MAR 11.4896 12.8 SRX ----------------------------------------------------------------------------- BL LACERTAE BL Lac (prototype of BL Lac type objects) appears to be active (see also News Flash No. 174) as indicated by the following observations: AAVSO Observer UT Mag. Initials MAR 05.5285 15.2: HSG MAR 08.5090 14.7 HSG MAR 10.5278 13.5 HSG Please keep a close eye on this star for astronomers have been observing this object recently with the Compton Gamma-Ray Observatory. An AAVSO 'f' scale standard chart for BL Lac is available at the following ftp site: ftp.aavso.org (198.116.78.2), in pub/charts/lac/bl_lac/ The chart may also be accessed through our web site at the following address: http://www.aavso.org ----------------------------------------------------------------------------- TZ PERSEI The dwarf nova type (Z Cam subclass) cataclysmic variable TZ Per appears to be in outburst, as indicated by the following observations: AAVSO Observer UT Mag. Initials MAR 03.1229 14.6 HSG MAR 08.844 14.2: PYG MAR 09.950 12.9 PYG ----------------------------------------------------------------------------- VZ PYXIDIS The dwarf nova type (SU UMa subclass) cataclysmic variable VZ Pyx appears to be undergoing an outburst, as indicated by the following observations: AAVSO Observer UT Mag. Initials MAR 09.4778 <14.2 SRX MAR 10.4722 12.8 SRX MAR 10.6306 12.8 SRX MAR 11.4583 13.4 SRX ----------------------------------------------------------------------------- UZ SERPENTIS The dwarf nova type (SS Cyg subclass) cataclysmic variable UZ Ser appears to be in outburst, as indicated by the following observations: AAVSO Observer UT Mag. Initials MAR 08.7507 <14.5 SRX MAR 09.7431 14.0 SRX MAR 09.7847 13.8 SRX MAR 10.7201 13.5 SRX ----------------------------------------------------------------------------- We thank the following contributors for the data that they have provided for this News Flash: HSG - G. Hanson, USA PYG - G. Poyner, England SRX - R. Stubbings, 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 ________________________________________________________________________________ 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 sending a message to: observations@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 We look forward to including your observations in future editions of AAVSO NEWS FLASH! _______________________________________________________________________________