THE ASTRONOMER Electronic Circular No 700 1993 Jan 5 20.20UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP,England. Telephone/FAX(0256)471074 Int:+44256471074 TELEX: 9312111261 Answerback: TA G TELECOM GOLD: 10074:MIK2885 GMH at UK.AC.RUTHERFORD.STARLINK.ASTROPHYSICS STARLINK: RLSAC::GMH GMH at UK.AC.CAM.ASTRONOMY.STARLINK STARLINK: CAVAD::GMH ------------------------------------------------------------------- COMET MUELLER (1993a) Jean Mueller reports her discovery of a comet on a plate taken during the course of the second Palomar Sky Survey with the 1.2-m Oschin Schmidt Telescope, and provides the following positions from trails. The object is condensed with a prominent coma and a faint tail to the south. 1993 UT R.A. (2000) Decl. m1 Jan. 2.40833 9 46 45.34 +47 02 27.8 15.5 2.45347 9 46 42.62 +47 03 05.2 3.52708 9 45 28.25 +47 20 23.7 3.54792 9 45 27.11 +47 20 37.7 IAUC 5687 T LEONIS (UGSU) Patrick Schmeer, Germany reports the following observations: Jan 1.166 UT, (13.9 ; 2.124, 10.4 ; 3.119, 10.7 ;4.130 UT, 10.9 and comments that this is a rather faint superoutburst. Taichi Kato, Japan, provides confirmation and additional information: "CCD observations of T Leo on Jan. 2 indicate this star was rapidly fading. The observations were performed from 2.750 to 2.895 UT with the time resolution of 30 s. The sky was very clear and I could cover more than two full orbital cycles of this dwarf nova with typical error of single observations less than 0.01 mag. During this period, T Leo faded by 0.2 mag. Superimposed were hump features of 0.1 mag with maxima at 2.807 and 2.865 UT. The interval suggests this variation is not caused by superhumps, but by orbital modulation. CCD photometry of T Leo was also obtained on Jan. 3. The following preliminary results are available: * The mean magnitude was V=11.6 (based on GSC V=11.9 star). * decline by 0.15 mag in 4 hr observation * Hump structures with an amplitude of 0.11 mag persisted. The hump maxima were seen at 3.762, 3.820, and 3.880 UT. The profile resembles superhumps (steeper rise). * The hump maxima are well represented by the following formula. Max UT = 2.806 + 0.05965 E The period is significantly longer (by 1.4%) than the orbital (0.058819) one, but is still different from the previously reported superhump period (0.06411). MARS Further to the report on E698, part of the message from Ken Irving was lost in transmission to us. The observer was evidently Cliff Meredith. Guy M Hurst