Electronic Telegram No. 5169 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 C/2022 P3 (ZTF) Bryce T. Bolin (Infrared Processing and Analysis Center, California Institute of Technology; and Goddard Space Flight Center), on behalf of the "Zwicky Transient Facility (ZTF) Collaboration", reports the discovery of a comet in CCD images taken using the 1.2-m Schmidt telescope at Palomar; the object was initially identified as having a possible cometary appearance in images taken on Aug. 2.49 UT (assisted by "artificial intelligence" using the "Tails" pipeline). The comet showed a coma about 4" wide and a broad tail about 7" long in p.a. about 220 degrees in ZTF images taken both on Aug. 2 and 5; ZTF r-band photometry measured in 5"-radius apertures and calibrated to the PS1 magnitude system are 19.0 and 18.9 on the two nights, respectively. The discovery observations are tabulated below. 2022 UT R.A. (2000) Decl. Mag. Aug. 2.48913 5 53 27.93 +24 54 39.3 19.4 2.49149 5 53 28.18 +24 54 41.9 19.1 2.49384 5 53 28.43 +24 54 44.1 19.1 2.49622 5 53 28.66 +24 54 46.1 19.2 2.49858 5 53 28.86 +24 54 48.4 19.0 5.49240 5 58 09.02 +25 37 58.3 19.3 5.49481 5 58 09.23 +25 38 00.3 19.3 5.49725 5 58 09.46 +25 38 02.5 19.1 5.50211 5 58 09.90 +25 38 06.5 19.3 After the comet was posted on the Minor Planet Center's PCCP webpage, other CCD astrometrists have commented on the cometary appearance. Fourteen stacked 60-s exposures taken remotely by H. Sato (Bunkyo-ku, Tokyo, Japan) with a 0.51-m f/6.8 astrograph located at Mayhill, NM, USA, on Aug. 8.45-8.46 UT show a strongly condensed coma 8" in diameter with no tail; the magnitude was 18.8 as measured within a circular aperture of radius 4".9. Fifty-two stacked 30-s exposures taken by L. Buzzi, Varese, Italy, with a 0.84-m f/3.5 reflector in fair seeing on Aug. 20.1 show a condensed coma 7" wide and elongated in p.a. 290 deg; the magnitude was given as 18.5. The available astrometry appear on MPEC 2022-R132. The following parabolic orbital elements by S. Nakano (Central Bureau) are from 83 observations spanning 2022 Aug. 2-Sept. 7 (mean residual 0".5). T = 2022 July 27.66357 TT Peri. = 0.20013 Node = 72.25981 2000.0 q = 2.5655468 AU Incl. = 59.48727 The following ephemeris by the undersigned from the above orbital elements uses photometric power-law parameters H = 13.0 and 2.5n = 8 for the magnitudes. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2022 08 09 06 03.62 +26 28.9 3.178 2.569 45.4 16.3 18.8 2022 08 14 06 11.44 +27 42.3 3.129 2.572 48.5 17.2 18.8 2022 08 19 06 19.27 +28 56.8 3.079 2.577 51.7 18.0 18.7 2022 08 24 06 27.10 +30 12.8 3.027 2.582 54.9 18.7 18.7 2022 08 29 06 34.92 +31 30.6 2.974 2.589 58.2 19.4 18.7 2022 09 03 06 42.72 +32 50.3 2.921 2.597 61.6 20.0 18.6 2022 09 08 06 50.48 +34 12.5 2.867 2.605 64.9 20.5 18.6 2022 09 13 06 58.20 +35 37.3 2.813 2.615 68.4 21.0 18.6 2022 09 18 07 05.87 +37 05.1 2.759 2.626 71.9 21.3 18.6 2022 09 23 07 13.46 +38 36.2 2.706 2.638 75.4 21.6 18.5 2022 09 28 07 20.96 +40 10.8 2.653 2.651 79.0 21.8 18.5 2022 10 03 07 28.35 +41 49.3 2.602 2.665 82.6 21.9 18.5 2022 10 08 07 35.60 +43 31.7 2.553 2.680 86.3 21.8 18.5 2022 10 13 07 42.68 +45 18.3 2.505 2.696 89.9 21.7 18.4 2022 10 18 07 49.57 +47 09.1 2.461 2.712 93.6 21.5 18.4 2022 10 23 07 56.23 +49 04.0 2.420 2.730 97.2 21.2 18.4 2022 10 28 08 02.59 +51 02.9 2.382 2.748 100.8 20.8 18.4 2022 11 02 08 08.61 +53 05.5 2.349 2.768 104.4 20.3 18.4 2022 11 07 08 14.23 +55 11.1 2.320 2.788 107.8 19.8 18.4 2022 11 12 08 19.36 +57 19.2 2.296 2.809 111.1 19.2 18.4 2022 11 17 08 23.91 +59 29.0 2.277 2.831 114.2 18.6 18.4 2022 11 22 08 27.74 +61 39.4 2.265 2.853 117.1 18.0 18.4 2022 11 27 08 30.71 +63 49.3 2.258 2.876 119.6 17.4 18.4 2022 12 02 08 32.65 +65 57.3 2.257 2.900 121.8 16.8 18.5 2022 12 07 08 33.33 +68 02.0 2.262 2.925 123.6 16.3 18.5 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2022 CBAT 2022 September 8 (CBET 5169) Daniel W. E. Green