Electronic Telegram No. 5312 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 V2 (PANSTARRS) R. Weryk, Department of Physics and Astronomy, University of Western Ontario, reports the discovery of another comet in images obtained on Nov. 4 with the Pan-STARRS2 (first four observations tabulated below) and Pan-STARRS1 (last two observations tabulated below) 1.8-m Ritchey-Chretien reflectors at Haleakala, Hawaii. Four 45-s w-band Pan-STARRS2 survey images taken in poor (1".6) seeing on Nov. 4.5 UT show a condensed coma of size 2".0 (full-width-at-half-maximum) with no obvious tail. 2023 UT R.A. (2000) Decl. Mag. Nov. 4.46638 3 15 10.14 + 6 45 55.5 20.5 4.47885 3 15 09.69 + 6 45 55.0 20.5 4.49134 3 15 09.24 + 6 45 54.6 20.6 4.50372 3 15 08.81 + 6 45 53.8 20.6 4.56749 3 15 06.57 + 6 45 50.9 20.3 4.56831 3 15 06.54 + 6 45 51.0 20.0 Pan-STARRS1 observations were subsequently identified in the Minor Planet Center's "isolated tracklet file" from Oct. 15.5 UT (mag 21.4-21.8), as were Pan-STARRS2 observations from Oct. 18.5 (mag 21.2-21.4) and Oct. 24.4 (mag 20.7-21.0). Earlier pre-discovery Pan-STARRS2 observations were later reported from Sept. 19.6 (mag 22.3), as were Pan-STARRS1 observations from Oct. 6.5 (mag 21.2-21.9) After the comet was posted on the Minor Planet Center's PCCP webpage, H. Sato (Bunkyo-ku, Tokyo, Japan) reports that eight stacked 120-s CCD exposures taken remotely with a iTelescope 0.51-m f/6.8 astrograph located at the "Deep Sky Chile" observatory in Rio Hurtado, Chile, show a strongly condensed coma 5" in diameter with no tail; the magnitude was 20.1 as measured within a circular aperture of radius 2".8. The available astrometry appears on MPEC 2023-V108. The following elliptical orbital elements by S. Nakano (Central Bureau) are from 34 observations spanning 2023 Sept. 19-Nov. 6 (mean residual 0".2). These suggest that the comet passed 0.0030 AU from Saturn on 2018 Feb. 3 UT, which would have greatly changed its orbit. T = 2024 Feb. 3.93213 TT Peri. = 330.49786 e = 0.5726673 Node = 95.52858 2000.0 q = 3.1043014 AU Incl. = 9.87300 a = 7.2643670 AU n = 0.05033933 P = 19.58 years The following ephemeris by the undersigned from the above orbital elements uses photometric power-law parameters H = 14.0 and 2.5n = 8 for the magnitudes. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2023 10 23 03 21.49 +06 59.1 2.260 3.197 156.5 7.1 19.8 2023 11 02 03 16.54 +06 47.9 2.210 3.180 165.5 4.5 19.7 2023 11 12 03 10.78 +06 42.4 2.187 3.165 169.2 3.4 19.7 2023 11 22 03 04.92 +06 45.1 2.193 3.152 163.2 5.2 19.7 2023 12 02 02 59.69 +06 58.0 2.226 3.140 153.6 8.0 19.7 2023 12 12 02 55.71 +07 21.9 2.284 3.130 143.4 10.8 19.8 2023 12 22 02 53.47 +07 56.8 2.364 3.121 133.2 13.3 19.8 2024 01 01 02 53.22 +08 41.8 2.462 3.114 123.4 15.3 19.9 2024 01 11 02 55.05 +09 35.4 2.575 3.109 114.1 16.8 20.0 2024 01 21 02 58.93 +10 35.9 2.699 3.106 105.2 17.8 20.1 2024 01 31 03 04.72 +11 41.4 2.830 3.104 96.8 18.4 20.2 2024 02 10 03 12.25 +12 50.2 2.965 3.105 88.8 18.5 20.3 2024 02 20 03 21.35 +14 00.7 3.101 3.107 81.1 18.3 20.4 2024 03 01 03 31.82 +15 11.3 3.237 3.110 73.8 17.8 20.5 2024 03 11 03 43.49 +16 20.6 3.370 3.116 66.8 17.0 20.6 2024 03 21 03 56.22 +17 27.5 3.498 3.123 60.1 16.1 20.7 2024 03 31 04 09.85 +18 30.7 3.620 3.132 53.6 14.9 20.8 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2023 CBAT 2023 November 8 (CBET 5312) Daniel W. E. Green