Electronic Telegram No. 1721 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions) CBAT@CFA.HARVARD.EDU (science) URL http://www.cfa.harvard.edu/iau/cbat.html COMET C/2009 E1 (ITAGAKI) H. Yamaoka, Kyushu University, reports the discovery of a comet with coma diameter about 70" on CCD images taken by Koichi Itagaki (Yamagata, Japan) with a 21-cm f/3 reflector (diameter of field 2.2 deg), using software by H. Kaneda to detect moving objects automatically. The original times for the two discovery images (as well as the first four follow-up images taken at the same location with a 30-cm f/7.8 reflector) were later corrected and relayed by S. Nakano (Sumoto, Japan), who notes that the comet is diffuse with weak condensation and a hint of tail toward the south, measuring total mag 11.9 from an image taken on Mar. 14.424 UT. Available CCD astrometry, including that sent to the Central Bureau after posting on the Minor Planet Center's NEOCP webpage: CK09E010 1C2009 03 14.41509 02 48 07.10 +08 23 31.0 12.8 D94 CK09E010 1C2009 03 14.41522 02 48 06.88 +08 23 33.3 12.8 D94 CK09E010 1C2009 03 14.42556 02 48 05.43 +08 24 19.4 D94 CK09E010 1C2009 03 14.42872 02 48 05.06 +08 24 34.2 D94 CK09E010 1C2009 03 14.43199 02 48 04.57 +08 24 47.3 D94 CK09E010 1C2009 03 14.44446 02 48 02.82 +08 25 45.6 D94 CK09E010 C2009 03 15.03862 02 46 33.02 +09 11 30.4 16.6 H55 CK09E010 C2009 03 15.04076 02 46 32.69 +09 11 40.3 16.4 H55 CK09E010 C2009 03 15.04279 02 46 32.37 +09 11 49.4 16.6 H55 CK09E010 C2009 03 15.10722 02 46 22.59 +09 16 42.3 14.6 H06 CK09E010 C2009 03 15.11760 02 46 21.01 +09 17 29.7 16.1 854 CK09E010 C2009 03 15.11923 02 46 20.76 +09 17 36.8 14.6 H06 CK09E010 C2009 03 15.12120 02 46 20.44 +09 17 45.5 15.9 854 CK09E010 C2009 03 15.12420 02 46 20.01 +09 17 59.3 15.9 854 CK09E010 C2009 03 15.39647 02 45 39.24 +09 38 24.5 349 CK09E010 C2009 03 15.39704 02 45 39.18 +09 38 27.2 349 CK09E010 C2009 03 15.40429 02 45 38.05 +09 38 59.5 13.3 D94 CK09E010 C2009 03 15.40458 02 45 38.04 +09 39 01.1 349 CK09E010 C2009 03 15.40534 02 45 37.89 +09 39 03.6 349 CK09E010 C2009 03 15.40687 02 45 37.65 +09 39 10.7 10.8 349 CK09E010 C2009 03 15.40792 02 45 37.58 +09 39 16.5 D94 CK09E010 C2009 03 15.41272 02 45 36.80 +09 39 36.7 D94 CK09E010 C2009 03 15.41578 02 45 36.29 +09 39 50.5 D94 CK09E010 C2009 03 15.41639 02 45 36.29 +09 39 54.2 900 CK09E010 C2009 03 15.41993 02 45 35.70 +09 40 09.5 D94 CK09E010 C2009 03 15.42025 02 45 35.71 +09 40 11.2 900 CK09E010 C2009 03 15.42291 02 45 35.30 +09 40 23.2 D94 CK09E010 C2009 03 15.42443 02 45 35.09 +09 40 30.0 900 CK09E010 C2009 03 15.42829 02 45 34.47 +09 40 47.3 14.6 900 CK09E010 C2009 03 15.45943 02 45 29.80 +09 43 05.8 349 CK09E010 C2009 03 15.46067 02 45 29.63 +09 43 11.8 349 CK09E010 C2009 03 15.46193 02 45 29.46 +09 43 16.9 349 CK09E010 C2009 03 15.50017 02 45 23.56 +09 46 06.9 12.4 367 CK09E010 C2009 03 15.50156 02 45 23.42 +09 46 12.7 12.6 367 CK09E010 C2009 03 15.50295 02 45 23.16 +09 46 18.6 12.6 367 Observer information, listed chronologically by observer code: D94 K. Itagaki (Takanezawa, Tochigi, Japan). Long. = 139d59'46".4 east, Lat. = +36d37'40".2, elevation 200 m, rho cos phi' = 0.80351, rho sin phi' = +0.59335. Measurer Hiroshi Kaneda (Sapporo, Japan). H55 R. Holmes (Charleston, IL, USA, 0.61-m f/4.5 astrograph). Measurer H. Devore. USNO-B1.0 catalogue for astrometry and photometry. Ten co-added exposures reveal a nuclear condensation 28" in diameter and a diffuse coma 54".8 in diameter (no tail). H06 E. Guido, G. Sostero, and P. Camilleri (observing remotely with a 0.25-m f/3.4 reflector near Mayhill, NM, USA). UCAC-2 catalogue for astrometry and photometry. Thirty co-added 30-s unfiltered exposures show a bright inner coma with diameter of about 1'.4, and a faint external halo nearly 4' in diameter (total mag about 11.0). 854 J. E. McGaha (near Tucson, AZ, USA, 0.36-m f/10 Schmidt-Cassegrain reflector). USNO-A2.0 catalogue for astrometry and photometry. Fifteen stacked 30-s images show a 42"-diameter bright coma with a fan-shaped tail spanning 60 deg (90" long at p.a. 70 deg, the center of the fan). Red magnitudes from single 30-s exposures within specific photometric apertures: 30", 14.1; 60", 13.1; 90", 12.2; 180", 11.3. 349 K. Kadota (Ageo, Saitama-ken, Japan, 0.25-m f/5 reflector). On Mar. 15.41, bright coma of diameter 3'.8, with strong central condensation and no tail. Tycho-2 catalogue used for magnitude. 900 Y. Ikari (Moriyama, Shiga-ken, Japan, 0.26-m f/7 reflector). Communicated by Nakano. 367 H. Abe (Yatsuka-cho, Shimane-ken, Japan, 0.26-m f/6 reflector). Communicated by Nakano. The following preliminary parabolic orbital elements are by Nakano from 33 of the above observations: T = 2009 Apr. 7.337 TT Peri. = 46.988 Node = 105.823 2000.0 q = 0.60849 AU Incl. = 128.582 M. Kusiak, Astronomical Observatory, Jagiellonian University, reports that comet C/2009 E1 is visible in SOHO SWAN ultraviolet images at website URL http://sohowww.nascom.nasa.gov/data/summary/swan/swan-images.html. He measures the following coordinates in the images (x and y being 0.0 at the upper left): Mar. 5, x = 504, y = 327 (R.A. = 2h59m, Decl. = -3o50'); Mar. 11, x = 510, y = 311 (R.A. = 2h53m, Decl. = +4o00'); Mar. 12, x = 511, y = 307 (R.A. = 2h50m, Decl. = +5o50'). He estimates the total mag at about 11.0. Visual total-magnitude and coma-diameter estimates for C/2009 E1: Mar. 14.85 UT, 9.6, 4'.5 (J. J. Gonzalez, Leon, Spain, 0.20-m reflector; zodiacal light); 15.103, 10:, 3' (A. Hale, Cloudcroft, NM, U.S.A., 41-cm reflector; clouds; small condensed area within a diffuse coma). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2009 CBAT 2009 March 15 (CBET 1721) Daniel W. E. Green