------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 2417 2008 Feb 03 13.20UT 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 Backup: gmh@wdcc1.bnsc.rl.ac.uk WORLD WIDE WEB http://www.theastronomer.org ------------------------------------------------------------------- COMET C/2008 C1 (CHEN-GAO) J. Beize, Beijing Technology and Business University, reports on IAUC 8915 the discovery of a comet by Tao Chen, China on a CCD image taken on 2008 Feb. 1 by Xing Gao (Urumqi, Xinjiang province) with a wide-field 7-cm, 200-mm-f.l., f/2.8 camera lens (+ Canon 350D camera) at Gao's Xingming Observatory, Mt. Nanshan, in the course of a nova survey. Subsequently earlier images of the magnitude 14 comet were found taken by Gao on Jan 30 and also Jan 31 when it was about magnitude 13.5. An apparent brightening had been recorded reaching magnitude 12.0 by Feb 2. Following posting on the Minor Planet Center's 'NEOCP' webpage, numerous CCD astrometrists have commented on the comet's appearance, including J. Lacruz, Madrid, Spain (0.40-m Ritchey- Chretien reflector, Feb. 2.8 UT; condensed inner coma of diameter 20"; outer coma of diameter 50", slightly elongated in p.a. 35 deg). Very approximate positions from wide-field imaging: 2008 UT R.A. (2000) Decl. Mag. Observer Jan. 30.91573 22 50 58 +62 15.2 14.0 Gao 31.92406 22 57 08 +62 13.9 13.5 " Feb. 1.66713 23 03 48 +62 12.4 13.0 " 2.64737 23 09 34 +62 11.6 12.0 " Brian Marsden has reported on M.P.E.C. 2008-C16 the following orbital elements and ephemeris: T 2008 Apr. 17.216 TT MPC q 1.26927 (2000.0) P Q Peri. 180.781 -0.613111 -0.365072 Node 307.451 +0.729510 +0.078688 e 1.0 Incl. 61.943 +0.303168 -0.927648 >From 37 observations 2008 Feb. 1-3. Ephemeris: Date TT R A (2000) Decl. Delta r Elong. Phase m1 2008 01 30 22 47.72 +62 15.6 1.522 1.719 83.6 34.7 13.3 2008 02 04 23 17.97 +62 07.8 1.481 1.672 82.7 35.8 13.1 2008 02 09 23 50.42 +61 44.5 1.443 1.627 81.7 36.9 12.9 2008 02 14 00 24.45 +61 00.7 1.409 1.583 80.6 38.0 12.7 2008 02 19 00 59.22 +59 52.1 1.379 1.541 79.3 39.1 12.6 2008 02 24 01 33.75 +58 16.0 1.354 1.500 77.9 40.2 12.4 2008 02 29 02 07.13 +56 11.4 1.334 1.463 76.4 41.2 12.3 2008 03 05 02 38.65 +53 39.4 1.321 1.427 74.7 42.1 12.1 2008 03 10 03 07.88 +50 43.1 1.314 1.395 72.9 42.9 12.0 2008 03 15 03 34.65 +47 26.7 1.314 1.366 71.0 43.5 11.9 2008 03 20 03 58.98 +43 55.0 1.321 1.340 69.0 44.0 11.9 2008 03 25 04 21.06 +40 13.0 1.334 1.318 67.0 44.2 11.8 Guy M Hurst