BELGIAN ASTRONOMICAL SOCIETY V.V.S. - Working Group Variable Stars Cataclysmic Variables Circular No.129 1997, February 20 Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM Internet: tvanmuns@innet.be TEL. 32-11-831504 CBA Belgium Web Page : http://www.astro.columbia.edu/~cba/be =================================================================== T Leo [UGSU, 10B - 15.7B] ========================= Robert Modic, USA has detected an outburst of T Leo, as announced on vsnet. Following observations, confirming the outburst, have been received so far : 1997 Feb 18.697 UT, <13.6 (Watanabe, VSOLJ, seq: GSC); Feb 19.17 UT, <13.6 (P. Schmeer, Germany); Feb 19.276 UT, 12.2 (R. Modic, USA); Feb 19.347 UT, 11.9 (R. Modic); Feb 19.489 UT, 10.9 (G. Hanson, USA); Feb 19.500 UT, 10.9 (G. Hanson); Feb 19.525 UT, 10.8 (G. Hanson); Feb 19.533 UT, 10.4 (Watanabe); Feb 19.549 UT, 10.7 (G. Hanson); Feb 20.111 UT, 10.4 (Schmeer); The previous outburst of T Leo was observed on 1995, November 13 by P. Schmeer [CVC 70], when the object reached mag. 10.4. It was a poorly observed outburst [CVC 73]. T Leo is a remarkable object, in the sense that on a couple of occasions, it has shown rebrightenings after outbursts (maybe of a similar nature as the ones exhibited by GO Com, V1028 Cyg and others). These secondary maxima of T Leo can be almost as bright as the primary outburst, but last for only one day or so. Since there is considerable interest in a detailed study of this phenomenon, T Leo has been added to the CVAP programme in May 1995. Our primary objective was to monitor a number of future outbursts intensively in order to detect and follow-up these secondary maxima [CVC 38]. We encourage our observers to continue monitoring this object during its present outburst in the period after the initial decline. With a little luck, the fading will occur without moonlight inter- vening, hence providing an excellent opportunity to study T Leo, which is now well placed in the evening sky. Tonny Vanmunster