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: V1159 Ori, YZ Cnc, GK Per, No. 4 TT Boo, U Gem, UV Per March 18, 1996 ________________________________________________________________________________ V1159 ORIONIS The dwarf nova type (SU UMa subclass) cataclysmic variable V1159 Ori is in superoutburst as indicated by the following observations: UT JD Mag. Observer MAR 2.2201 2450144.7201 <12.4 (W. Dillon, USA) MAR 8.1160 2450150.616 <13.6 (Dillon) MAR 9.1097 2450151.6097 <13.6 (A. Dill, USA) MAR 10.0514 2450152.5514 13.4 (G. Chaple, USA) MAR 10.1035 2450152.6035 13.4 (R. Harvan, USA) MAR 10.1368 2450152.6368 13.7: (Dillon) MAR 10.1611 2450152.6611 13.6 (Dill) MAR 11.0521 2450153.5521 13.8 (J. Bortle, USA) MAR 12.8021 2450155.3021 <12.4 (M. Kohl, Switzerland) MAR 16.989 2450159.489 13.088 CCDV(R. Zissell, USA) MAR 17.028 2450159.528 13.036 CCDV(Zissell) MAR 17.064 2450159.564 13.078 CCDV(Zissell) MAR 17.0674 2450159.5674 12.6 (Bortle) MAR 17.12 2450159.62 12.6 (K. Millyard, Canada) MAR 18.0396 2450160.5396 12.8 (Bortle) Observers with CCD's are strongly recommended to observe this star every three minutes to detect superhumps. William Liller, Gary Walker, and Ron Zissell have already provided excellent CCD observations which we are analyzing for superhump periodicity. Please monitor this star closely. ------------------------------------------------------------------------------ YZ CANCRI IN OUTBURST The dwarf nova type (SU UMa subclass) cataclysmic variable YZ Cnc has gone into a superoutburst as indicated by the following observations: UT JD Mag. Oberver MAR 8.85 2450151.35 13.4: (M. Verdenet, France) MAR 9.1222 2450151.6222 13.6: (A. Dill, USA) MAR 12.0778 2450154.5778 14.8 (J. Bortle, USA) MAR 13.0715 2450155.5715 14.2 (S. Tracy, USA) MAR 14.0542 2450156.5542 11.9 (Tracy) MAR 15.0653 2450157.5653 11.9 (Tracy) MAR 16.1264 2450158.6264 11.0 (M. Heifner, USA) MAR 17.0757 2450159.5757 11.4 (Bortle) MAR 18.0472 2450160.5472 10.9 (Tracy) ------------------------------------------------------------------------------ GK PERSEI The minor outburst of the old nova GK Persei continues as indicated by the following observations: UT JD Mag. Observer MAR 13.008 2450155.508 11.2 (J. McKenna, USA) MAR 13.1049 2450155.6049 11.0 (M. Heifner, USA) MAR 13.810 2450156.31 11.0 (A. Diepvens, Belgium) MAR 13.8479 2450156.3479 10.9 (M. Kohl, Switzerland) MAR 14.796 2450157.296 11.1 (Diepvens) MAR 15.2813 2450157.7813 10.9 (R. Royer, USA) MAR 16.0542 2450158.5542 11.1 (C. Stephan, USA) MAR 16.1028 2450158.6028 10.7 (Heifner) MAR 16.1139 2450158.6139 11.5 (W. Kaminski, USA) MAR 16.1750 2450158.675 10.9 (T. Burrows, USA) MAR 17.0215 2450159.5215 10.7 (M. A. Komorous, Canada) MAR 17.0368 2450159.5368 11.8 (J. Bortle, USA) MAR 17.13 2450159.63 10.7 (K. Millyard, Canada) MAR 17.4229 2450159.9229 10.5 (J. Griese, USA) MAR 17.8854 2450160.3854 10.6 (K. Medway, England) MAR 18.0340 2450160.534 11.6 (Bortle) MAR 18.0521 2450160.5521 11.2 (Stephan) MAR 18.1632 2450160.6632 11.0 (Burrows) There is quite a bit of scatter between observer estimates. When reporting your observations, please include the comparison stars used in making the estimates and indicate the source, scale, and date of the chart used. The XTE satellite has been monitoring this star several times in the past few weeks and will continue to do so, so please keep a very close eye on the minor outburst of this old nova. ------------------------------------------------------------------------------ TT BOOTIS The dwarf nova type (SU Uma subclass) cataclysmic variable TT Boo has been going through a superoutburst as first reported by Michel Verdenet on March 9 and also by observers through vsnet. The star is now slowly fading from this outburst. UT JD Mag. Observer MAR 9.99 2450152.49 12.2 (M. Verdenet, France) MAR 15.2944 2450157.7944 13.3 (T. Burrows, USA) MAR 17.0979 2450159.5979 13.9 (J. Bortle, USA) MAR 18.0611 2450160.5611 14.0 (Bortle) ------------------------------------------------------------------------------ U GEMINORUM The recent outburst of U Gem that started on March 3rd has now ended as indicated by the following observations: UT JD Mag. Observer MAR 15.0590 2450157.559 12.6 (S. Tracy, USA) MAR 15.2500 2450157.75 12.2 (T. Burrows, USA) MAR 15.2639 2450157.7639 12.7 (R. Royer, USA) MAR 16.1222 2450158.6222 12.8 (M. Heifner, USA) MAR 16.1951 2450158.6951 13.0 (Burrows) MAR 17.038 2450159.538 13.8 (R. Zissell, USA) MAR 17.0736 2450159.5736 13.6 (J. Bortle, USA) MAR 18.0451 2450160.5451 13.8 (Tracy) MAR 18.0465 2450160.5465 13.7 (Bortle) MAR 18.1076 2450160.6076 <13.8 (W. Clark, USA) ------------------------------------------------------------------------------ UV PERSEI The recent outburst of UV Per (see also News Flash No. 3) was a narrow one as indicated by the following observations: UT JD Mag. Observer MAR 12.057 2450154.557 18.2 (R. Zissell, USA) MAR 14.836 2450157.336 11.9 (E. Broens, Belgium) MAR 14.844 2450157.344 12.3 (A. Diepvens, Belgium) MAR 15.1632 2450157.6632 12.3 (T. Burrows, USA) MAR 15.2118 2450157.7118 12.3 (Burrows) MAR 16.1056 2450158.6056 12.7 (M. Heifner, USA) MAR 16.1479 2450158.6479 13.0 (Burrows) MAR 17.0146 2450159.5146 14.0 (J. Griese, USA) MAR 17.018 2450159.518 14.01 CCDV (Zissell) MAR 17.0361 2450159.5361 13.9 (J. Bortle, USA) MAR 18.1486 2450160.6486 <14.1 (Burrows) This star is now back to minimum. ------------------------------------------------------------------------------ Please monitor these objects closely and phone-in, fax, or e-mail your observations to the AAVSO. Good observing! Janet A. Mattei ________________________________________________________________________________ AAVSO NEWS FLASH is a new electronic publication of the AAVSO intended to provide observers with timely information on unusual variable star activity. The basis of the data in this publication will be the observations reported to AAVSO Headquarters. The AAVSO NEWS FLASH will not replace the AAVSO Alert Notice. It will be more frequent and shorter. If you would like to contribute to AAVSO NEWS FLASH, please send observations of unusual variable star activity to: observations@aavso.org Please include the words NEWS FLASH in the subject line of your message. If you are affiliated with a variable star organization besides the AAVSO, and you wish that group to be indicated with the observations that you provide, please give the specific name of the organization or group and its abbreviation. Those who wish to unsubscribe to NEWS FLASH may do so by sending a message directly 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! ________________________________________________________________________________