Electronic Telegram No. 5222 Central Bureau for Astronomical Telegrams Mailing address: Hoffman Lab 209; Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A. e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org) URL http://www.cbat.eps.harvard.edu/index.html Prepared using the Tamkin Foundation Computer Network COMET P/2023 B3 (PANSTARRS) R. Weryk, Department of Physics and Astronomy, University of Western Ontario, reports the discovery of another comet in images obtained with the Pan-STARRS2 1.8-m Ritchey-Chretien reflector at Haleakala on Jan. 23 UT (discovery observations tabulated below). 2023 UT R.A. (2000) Decl. Mag. Jan. 23.42579 9 27 26.85 +11 22 26.0 21.1 23.43791 9 27 26.47 +11 22 28.5 21.3 23.45009 9 27 26.07 +11 22 31.0 20.9 23.46233 9 27 25.66 +11 22 33.5 21.0 Weryk adds that three 60-s follow-up gri-band images taken on Jan. 24.57 UT with the 3.6-m Canada-France-Hawaii Telescope at Mauna Kea (queue observer H. Januszewski; coordinator T. Burdullis) show a very condensed head of size 1".2 (full-width-at-half-maximum) in 0".8 seeing with a broad tail > 6" long spanning p.a. 260-320 degrees. After the comet was posted on the Minor Planet Center's PCCP webpage, H. Sato (Bunkyo-ku, Tokyo, Japan) reported that twelve stacked 120-s CCD exposures taken remotely on Jan. 26.6 UT with a 0.51-m f/6.8 astrograph located at Siding Spring show a strongly condensed coma 8" in diameter with no tail; the magnitude was 20.0 as measured within a circular aperture of radius 4".9. The available astrometry appears on MPEC 2023-D10. The following elliptical orbital elements by S. Nakano (Central Bureau) are from 63 observations spanning 2023 Jan. 23-Feb. 15 (mean residual 0".4). While the orbital period has some uncertainty, it appears that the comet passed 0.12 AU from Jupiter in 2005 April. Nakano was unable to find additional observations in archival astrometry files. T = 2020 Aug. 27.22379 TT Peri. = 238.62098 e = 0.1277563 Node = 153.93297 2000.0 q = 3.9601619 AU Incl. = 9.20881 a = 4.5402014 AU n = 0.10188058 P = 9.67 years The following ephemeris by the undersigned from the above orbital elements uses photometric power-law parameters H = 10.0 and 2.5n = 10 for the magnitudes. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2023 01 16 09 31.11 +10 58.3 3.701 4.602 153.5 5.5 19.5 2023 01 26 09 26.08 +11 31.4 3.654 4.612 164.8 3.2 19.5 2023 02 05 09 20.52 +12 08.6 3.639 4.622 175.5 1.0 19.5 2023 02 15 09 14.86 +12 47.3 3.654 4.632 171.0 1.9 19.5 2023 02 25 09 09.56 +13 25.2 3.700 4.642 159.8 4.2 19.5 2023 03 07 09 05.04 +13 59.9 3.776 4.652 148.6 6.4 19.6 2023 03 17 09 01.63 +14 29.8 3.877 4.662 137.8 8.2 19.6 2023 03 27 08 59.54 +14 53.9 4.000 4.671 127.3 9.8 19.7 2023 04 06 08 58.88 +15 11.4 4.139 4.681 117.2 11.0 19.8 2023 04 16 08 59.64 +15 22.3 4.291 4.691 107.5 11.8 19.9 2023 04 26 09 01.78 +15 26.5 4.450 4.700 98.2 12.2 20.0 2023 05 06 09 05.18 +15 24.3 4.613 4.710 89.3 12.4 20.1 2023 05 16 09 09.71 +15 16.1 4.776 4.719 80.7 12.2 20.1 2023 05 26 09 15.24 +15 02.2 4.935 4.729 72.4 11.8 20.2 2023 06 05 09 21.63 +14 42.9 5.087 4.738 64.4 11.1 20.3 2023 06 15 09 28.73 +14 18.8 5.230 4.747 56.6 10.3 20.4 2023 06 25 09 36.43 +13 50.3 5.362 4.757 49.0 9.3 20.4 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2023 CBAT 2023 February 17 (CBET 5222) Daniel W. E. Green