THE ASTRONOMER Electronic Circular No 536 1991 June 4 19.59UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP, England. Telephone: (0256)471074 Int:+44256471074 Telex: 9312111261 Answerback: TA G JANET BOXES: GMH at UK.AC.CAM.ASTRONOMY.STARLINK or GUYH at UK.AC.SUSSEX.CLUSTER TELECOM GOLD: 10074:MIK2885 PRESTEL 256471074 ------------------------------------------------------------------- COMET LEVY (1991q) Further precise positions: 1991 UT R.A. (1950) Decl. Observer June 17.44271 1 56 08.88 +15 42 17.7 Helin 17.45660 1 56 12.66 +15 42 52.5 " 19.06875 2 03 36.00 +16 53 46.5 Vagnozzi 25.83166 2 35 25.40 +21 37 18.6 McNaught E. Helin, K. Lawrence, P. Rose, and J. Alu (Palomar). 0.46-m Schmidt telescope. Remeasurement of positions given on IAUC 5293. A. Vagnozzi (Santa Lucia Stroncone). Communicated by G. Forti. R. H. McNaught (Siding Spring). Uppsala Southern Schmidt telescope. Preliminary parabolic orbital elements by the undersigned from nine observations, June 14-25: T = 1991 July 7.670 ET Peri. = 40.741 Node = 329.596 1950.0 q = 0.99597 AU Incl. = 19.232 IAUC 5296 Ephemeris by Hurst using a program by Nick James: m = 7.5 + 5.0 log R + 10.0 log r Date R.A. (1950) Dec. R r Elong Mag. Motion h m o ' (AU) (AU) o "/hr P.A. 1991 July 4.00 3 15.34 +26 38.0 1.333 0.998 48.0 8.1 186 63 5.00 3 20.32 +27 11.0 1.337 0.997 47.8 8.1 185 64 6.00 3 25.31 +27 43.1 1.343 0.996 47.5 8.1 184 64 7.00 3 30.30 +28 14.3 1.348 0.996 47.3 8.1 182 65 8.00 3 35.31 +28 44.6 1.354 0.996 47.1 8.1 181 66 9.00 3 40.33 +29 13.9 1.359 0.996 46.9 8.2 179 66 10.00 3 45.36 +29 42.3 1.365 0.997 46.7 8.2 178 67 11.00 3 50.38 +30 9.7 1.371 0.998 46.5 8.2 176 68 12.00 3 55.41 +30 36.2 1.378 0.999 46.3 8.2 175 68 13.00 4 0.44 +31 1.7 1.384 1.000 46.2 8.2 173 69 14.00 4 5.47 +31 26.2 1.391 1.002 46.0 8.2 172 69 15.00 4 10.49 +31 49.8 1.398 1.004 45.9 8.2 170 70 16.00 4 15.51 +32 12.4 1.405 1.006 45.7 8.3 168 71 17.00 4 20.52 +32 34.0 1.412 1.009 45.6 8.3 167 71 18.00 4 25.52 +32 54.7 1.419 1.012 45.5 8.3 165 72 19.00 4 30.50 +33 14.4 1.427 1.015 45.3 8.3 163 73 20.00 4 35.47 +33 33.2 1.434 1.018 45.2 8.4 162 74 21.00 4 40.42 +33 51.0 1.442 1.022 45.1 8.4 160 74 22.00 4 45.35 +34 7.9 1.449 1.026 45.1 8.4 158 75 23.00 4 50.26 +34 23.9 1.457 1.030 45.0 8.4 157 76 24.00 4 55.14 +34 39.0 1.465 1.035 44.9 8.5 155 76 25.00 5 0.00 +34 53.2 1.473 1.039 44.9 8.5 153 77 26.00 5 4.84 +35 6.6 1.481 1.044 44.8 8.5 151 78 27.00 5 9.64 +35 19.1 1.489 1.050 44.8 8.6 150 78 28.00 5 14.41 +35 30.8 1.497 1.055 44.8 8.6 148 79 29.00 5 19.15 +35 41.6 1.505 1.061 44.7 8.6 146 80 30.00 5 23.85 +35 51.7 1.513 1.067 44.7 8.7 144 80 31.00 5 28.51 +36 1.0 1.522 1.073 44.7 8.7 143 81 IUE Campaign Thanks to all observers who contributed to the dwarf nova campaign during June. Janet Drew in Oxford tells us that our alerts relating to AH Herculis were the earliest received and permitted this star to be selected for monitoring by the IUE Guy M Hurst