------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 1742 2002 Feb 06 10.30UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074 INTERNET: GUY@TAHQ.DEMON.CO.UK GMH at AST.STAR.RL.AC.UK WORLD WIDE WEB http://www.theastronomer.org ------------------------------------------------------------------- COMET C/2002 C1 (IKEYA-ZHANG) Graham Wolf, Moera, Lower Hutt, New Zealand, has e-mailed the editor to report that he independently discovered this comet,(prior to seeing IAUC 7812), on 2002 Feb 2 at 10.08UT as a mag 8 diffuse object in Cetus, using a 0.18-m f5 Newtonian at x75. The estimated size of the coma was 0.6' x 0.5'. A fuller report will appear in 'The Astronomer' magazine. The latest orbital elements on MPEC 2002-C19, significantly change the ephemeris we published on TA E-Circular 1740: Orbital elements: C/2002 C1 (Ikeya-Zhang) T 2002 Mar. 18.537 TT MPC q 0.50839 (2000.0) P Q Peri. 33.768 -0.545419 -0.694717 Node 93.857 +0.626784 -0.709500 e 1.0 Incl. 28.033 +0.556471 +0.118229 >From 63 observations 2002 Feb. 1-4. Revised ephemeris by Guy Hurst using EPH.EXE by Nick James. The small solar elongation will make the comet quite difficult but the position appears to improve from April onwards: m = 8.5 + 5.0 log R + 10.0 log r Date R.A. (2000) Dec. R r Elong Mag. Motion h m o ' (AU) (AU) o "/hr P.A. 2002 Feb 5.00 0 14.96 -15 51.1 1.514 1.048 43.5 9.6 99 39 6.00 0 16.69 -15 19.9 1.502 1.031 43.0 9.5 101 39 7.00 0 18.43 -14 48.1 1.489 1.014 42.6 9.4 102 39 8.00 0 20.21 -14 15.7 1.477 0.996 42.1 9.3 104 38 9.00 0 22.00 -13 42.8 1.464 0.979 41.7 9.2 106 38 10.00 0 23.82 -13 9.1 1.451 0.962 41.3 9.1 108 38 11.00 0 25.66 -12 34.8 1.438 0.945 40.8 9.0 110 38 12.00 0 27.52 -11 59.9 1.424 0.928 40.4 8.9 112 38 13.00 0 29.41 -11 24.2 1.410 0.911 40.0 8.8 114 38 14.00 0 31.31 -10 47.7 1.396 0.894 39.6 8.7 116 37 15.00 0 33.24 -10 10.5 1.382 0.878 39.2 8.6 118 37 16.00 0 35.18 -9 32.5 1.367 0.861 38.8 8.5 120 37 17.00 0 37.15 -8 53.7 1.353 0.844 38.4 8.4 122 37 18.00 0 39.12 -8 14.0 1.338 0.827 38.1 8.3 124 36 19.00 0 41.12 -7 33.4 1.322 0.811 37.7 8.2 127 36 20.00 0 43.13 -6 51.9 1.307 0.794 37.4 8.1 129 36 21.00 0 45.15 -6 9.5 1.291 0.778 37.0 8.0 131 35 22.00 0 47.18 -5 26.0 1.275 0.762 36.7 7.8 134 35 23.00 0 49.22 -4 41.5 1.259 0.746 36.3 7.7 136 34 24.00 0 51.27 -3 55.9 1.242 0.730 36.0 7.6 138 34 25.00 0 53.32 -3 9.2 1.225 0.715 35.7 7.5 141 33 26.00 0 55.37 -2 21.3 1.208 0.699 35.4 7.4 143 32 27.00 0 57.41 -1 32.2 1.191 0.684 35.1 7.2 146 32 28.00 0 59.45 -0 41.9 1.173 0.669 34.8 7.1 148 31 2002 Mar 1.00 1 1.47 +0 9.6 1.156 0.655 34.5 7.0 151 30 2.00 1 3.48 +1 2.5 1.137 0.641 34.2 6.8 153 29 3.00 1 5.46 +1 56.8 1.119 0.627 33.9 6.7 156 28 4.00 1 7.41 +2 52.4 1.101 0.614 33.6 6.6 158 27 5.00 1 9.32 +3 49.5 1.082 0.602 33.4 6.5 161 26 6.00 1 11.19 +4 48.1 1.063 0.590 33.1 6.3 163 25 7.00 1 13.00 +5 48.1 1.044 0.578 32.9 6.2 166 24 8.00 1 14.74 +6 49.6 1.024 0.567 32.6 6.1 168 22 9.00 1 16.41 +7 52.6 1.005 0.557 32.4 6.0 170 21 Guy M Hurst