BELGIAN ASTRONOMICAL SOCIETY V.V.S. - Working Group Variable Stars Cataclysmic Variables Circular No.164 1998, March 25 Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM Internet: tvanmuns@innet.be TEL. 32-11-831504 CVC Web Page : http://www.cba.phys.columbia.edu/cvc =================================================================== TU Crt [UG, 12.1 - ?] ===================== CCD photometry of TU Crt, obtained on 1998, Mar 24/25 at CBA Belgium Observatory, during a 2.3 h run, shows the existence of a very weak periodic signal, which might be attributed to (developing) superhumps in this system. The period value, derived using the PDM technique, is 0.0843 +/- 0.004 d, while the mean semi-amplitude of the signal was 0.04 mag. Observations were made using a 0.25-m f/6.3 SCT and ST-7 CCD. We would like to stress the need for follow-up observations, to deter- mine if superhumps will fully grow in the next days and to establish a more accurate superhump period value (if the system proves to be an UGSU dwarf nova after all). Tonny Vanmunster