Electronic Telegram No. 5068 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/2021 V2 (FULS) David Carson Fuls, Lunar and Planetary Laboratory, University of Arizona, reports his discovery of a comet on CCD images taken with the Mt. Lemmon 1.5-m reflector on Nov. 7 (discovery observations tabulated below). Fuls noted a very condensed coma of diameter 6" and a tail 8" long in p.a. 270 degrees. 2021 UT R.A. (2000) Decl. Mag. Observer Nov. 7.30330 4 25 21.10 +18 39 45.3 19.7 Fuls 7.30843 4 25 20.97 +18 39 44.2 19.7 " 7.31356 4 25 20.82 +18 39 43.5 19.5 " 7.31868 4 25 20.69 +18 39 42.6 19.7 " 7.39590 4 25 18.58 +18 39 28.0 19.5 " 7.40660 4 25 18.30 +18 39 26.0 19.6 " 7.41736 4 25 18.00 +18 39 24.0 19.5 " 7.42831 4 25 17.70 +18 39 21.7 19.4 " R. Weryk, Department of Physics and Astronomy, University of Western Ontario, reports the independent discovery of this comet in images obtained with the Pan-STARRS2 1.8-m Ritchey-Chretien reflector at Haleakala less than an hour after Fuls took his images (but after the Mt. Lemmon observations were posted to the Minor Planet Center's webpage); Weryk relates that four 45-s w-band survey images taken on Nov. 7.35-7.38 UT in 1".1 seeing show a very condensed coma of size 1".5 (full-width-at-half-maximum) and magnitude 20.0-20.1 with a clear tail 5" long in p.a. 280 deg. The comet was previously observed with the Pan-STARRS1 1.8-m Ritchey-Chretien reflector at Haleakala on Aug. 7.6 and 20.6 (at mag 21.0-22.0), and with the Pan-STARRS2 telescope on Oct. 28.4 (at mag 20.2-20.5) -- all submitted under separate designations and in the MPC's "isolated tracklet file" (which is accessible publicly) but not recognized as cometary at the time of submission. The four 45-s w-band survey images from Oct. 28 were taken in 1".4 seeing and show a very condensed coma of size 1".7 (FWHM) and a 3" tail in p.a. 280 degrees. Weryk subsequently identified Pan-STARRS1 observations on Aug. 16.6 and Pan-STARRS2 observations of the comet at mag 19.8 from Oct. 31.6; on the latter night, four 45-s w-band survey iamges taken in 0".9 seeing show a very condensed coma of size 1".3 (FWHM) and a clear tail 5" long in p.a. 280 degrees. Sixteen 60-s CCD exposures taken remotely by H. Sato, Tokyo, Japan, on Nov. 8.21 UT with a 0.43-m f/6.8 astrograph located near Mayhill, NM, USA, show a strongly condensed coma 8" in diameter with no tail; the magnitude was 19.5 as measured within a circular aperture of radius 5".7. The available astrometry appears on MPEC 2021-V169. The following elliptical orbital elements by S. Nakano (CBAT) are from 34 observations spanning 2021 Aug. 7-Nov. 8 (mean residual 0".1); the formal error in the orbital period is +/- 3.2 days. These elements suggest that the comet passed 0.48 AU from Jupiter in 1970 July. Epoch = 2023 Jan. 16.0 TT T = 2023 Jan. 21.41386 TT Peri. = 259.83312 e = 0.6138202 Node = 232.28337 2000.0 q = 3.4963845 AU Incl. = 12.69378 a = 9.0537724 AU n = 0.03617926 P = 27.24 years Epoch = 2050 July 13.0 TT T = 2050 June 24.29275 TT Peri. = 259.27608 e = 0.6220211 Node = 231.94140 2000.0 q = 3.5296109 AU Incl. = 12.63878 a = 9.3381150 AU n = 0.03453944 P = 28.54 years The following ephemeris by the undersigned from the above orbital elements uses photometric power-law parameters H = 11.0 and 2.5n = 8 for the magnitudes. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2021 11 02 04 27.53 +18 56.0 3.753 4.647 151.2 5.9 19.2 2021 11 12 04 23.19 +18 24.8 3.653 4.606 162.2 3.8 19.1 2021 11 22 04 18.07 +17 51.8 3.583 4.564 172.9 1.5 19.0 2021 12 02 04 12.57 +17 18.4 3.543 4.524 173.5 1.4 19.0 2021 12 12 04 07.20 +16 46.3 3.534 4.483 162.7 3.7 19.0 2021 12 22 04 02.42 +16 17.4 3.554 4.443 151.5 6.1 18.9 2022 01 01 03 58.66 +15 53.3 3.601 4.403 140.4 8.2 18.9 2022 01 11 03 56.21 +15 35.1 3.671 4.364 129.6 10.0 18.9 2022 01 21 03 55.30 +15 23.3 3.759 4.325 119.2 11.5 19.0 2022 01 31 03 55.99 +15 18.0 3.860 4.287 109.2 12.5 19.0 2022 02 10 03 58.29 +15 18.8 3.970 4.249 99.7 13.2 19.0 2022 02 20 04 02.15 +15 24.7 4.085 4.212 90.6 13.6 19.1 2022 03 02 04 07.45 +15 34.8 4.199 4.175 81.8 13.6 19.1 2022 03 12 04 14.09 +15 47.8 4.311 4.139 73.5 13.3 19.1 2022 03 22 04 21.92 +16 02.6 4.416 4.104 65.5 12.8 19.1 2022 04 01 04 30.82 +16 18.1 4.513 4.069 57.8 12.0 19.1 2022 04 11 04 40.67 +16 33.1 4.599 4.035 50.4 11.0 19.2 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2021 CBAT 2021 November 9 (CBET 5068) Daniel W. E. Green