Electronic Telegram No. 5674 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/2026 C2 (PANSTARRS) R. Weryk, Department of Physics and Astronomy, University of Western Ontario, reports the discovery of another comet in images obtained on Feb. 13 with the Pan-STARRS1 1.8-m Ritchey-Chretien reflector at Haleakala. Four 45-s w-band survey images obtained in 1".1 seeing show no tail; a stack of the best two images show a very condensed head of size 1".8 (full-width-at- half-maximum). Pre-discovery observations obtained on Jan. 29 with the Pan-STARRS2 1.8-m Ritchey-Chretien reflector at Haleakala were identified later and are included with the discovery observations below. The last two observations on Feb. 13 were also made with the Pan-STARRS2 reflector. 2026 UT R.A. (2000) Decl. Mag. Jan. 29.61583 10 58 31.21 - 0 38 44.1 21.5 29.62364 10 58 31.09 - 0 38 43.3 21.5 29.63144 10 58 30.95 - 0 38 42.4 21.5 29.63924 10 58 30.83 - 0 38 41.5 21.4 Feb. 13.41203 10 52 41.28 + 0 10 57.4 20.0 13.43926 10 52 40.36 + 0 11 05.2 19.8 13.45288 10 52 39.90 + 0 11 09.0 19.9 13.52467 10 52 37.48 + 0 11 29.5 19.5 13.52532 10 52 37.44 + 0 11 29.8 19.6 Weryk adds that three stacked 60-s gri-band follow-up images obtained on Feb. 17.4 UT with the 3.6-m Canada-France-Hawaii Telescope at Mauna Kea (queue observer J. Silva; queue coordinator N. Manset) in 0".7-0".8 seeing show no obvious tail but confirms an asymmetric fuzziness (i.e., there is likely to be a tail present), with a condensed head of size 1".5 (FWHM). After the comet was posted to the Minor Planet Center's PCCP webpage, other astrometric observers commented on the cometary appearance. A. Aletti reports that one-hundred-seventy-eight 30-s CMOS unfiltered images obtained by F. Bellini, L. Buzzi, G. Galli, and himself on Feb. 14.89-14.93 UT with a 0.36-m f/8.6 reflector located at the Schiaparelli Southern Observatory, Hakos, Namibia, show a condensed 7" coma but no tail in 3".0 seeing. Twelve stacked 60-s CCD exposures taken remotely on Feb. 15.2 by H. Sato (Bunkyo-ku, Tokyo, Japan) using a 0.51-m f/6.8 astrograph located at Rio Hurtado, Chile, show a strongly condensed coma 6" in diameter with a tail 7" long toward p.a. 270 degrees; the magnitude was 20.0 as measured within a circular aperture of radius 2".9. The available astrometry appears on MPEC 2026-F121. The following two-body orbital elements by S. Nakano (Central Bureau) are from 148 observations spanning 2026 Jan. 29-Mar. 19 (mean residual 0".5). T = 2026 July 21.94719 TT Peri. = 11.03804 e = 0.3144610 Node = 190.55958 2000.0 q = 2.4356619 AU Incl. = 7.40130 a = 3.5529152 AU n = 0.14717255 P = 6.70 years The following ephemeris by Nakano from the above orbital elements uses photometric power-law parameters H = 13.5 and 2.5n = 10 for the magnitudes. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2025 12 01 10 35.93 +02 12.0 2.638 2.799 88.9 20.6 20.1 2025 12 11 10 44.21 +01 13.4 2.479 2.773 96.7 20.7 19.9 2025 12 21 10 50.98 +00 23.5 2.323 2.747 105.0 20.2 19.7 2025 12 31 10 55.99 -00 15.1 2.173 2.721 113.7 19.3 19.5 2026 01 10 10 59.02 -00 40.0 2.033 2.697 122.9 17.8 19.3 2026 01 20 10 59.86 -00 48.3 1.905 2.673 132.7 15.7 19.2 2026 01 30 10 58.43 -00 38.0 1.795 2.650 143.1 12.9 19.0 2026 02 09 10 54.86 -00 08.2 1.705 2.628 154.0 9.5 18.9 2026 02 19 10 49.52 +00 40.1 1.639 2.606 165.1 5.6 18.7 2026 03 01 10 43.10 +01 43.1 1.599 2.586 173.9 2.3 18.6 2026 03 11 10 36.53 +02 54.5 1.586 2.567 168.2 4.5 18.6 2026 03 21 10 30.76 +04 06.9 1.601 2.549 157.3 8.7 18.6 2026 03 31 10 26.66 +05 13.0 1.639 2.532 146.3 12.6 18.6 2026 04 10 10 24.80 +06 07.0 1.699 2.516 135.8 16.1 18.7 2026 04 20 10 25.45 +06 45.7 1.775 2.502 126.0 19.0 18.7 2026 04 30 10 28.64 +07 07.2 1.865 2.488 116.9 21.2 18.8 2026 05 10 10 34.19 +07 11.9 1.964 2.477 108.5 22.7 18.9 2026 05 20 10 41.85 +07 00.4 2.070 2.466 100.7 23.8 19.0 2026 05 30 10 51.35 +06 33.9 2.179 2.457 93.4 24.3 19.1 2026 06 09 11 02.39 +05 54.1 2.290 2.450 86.6 24.4 19.2 2026 06 19 11 14.74 +05 02.4 2.402 2.444 80.2 24.2 19.3 2026 06 29 11 28.17 +04 00.4 2.512 2.440 74.2 23.6 19.4 2026 07 09 11 42.49 +02 49.7 2.620 2.437 68.4 22.8 19.5 2026 07 19 11 57.59 +01 31.7 2.726 2.436 62.8 21.8 19.5 2026 07 29 12 13.33 +00 07.8 2.827 2.436 57.5 20.6 19.6 2026 08 08 12 29.62 -01 20.5 2.924 2.438 52.2 19.2 19.7 2026 08 18 12 46.40 -02 51.8 3.015 2.441 47.1 17.7 19.8 2026 08 28 13 03.63 -04 24.8 3.101 2.446 42.0 16.1 19.8 2026 09 07 13 21.24 -05 58.2 3.181 2.453 37.0 14.3 19.9 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2026 CBAT 2026 March 21 (CBET 5674) Daniel W. E. Green