Electronic Telegram No. 5282 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 O1 = P/2004 V3 (SIDING SPRING) Martin Masek, Institute of Physics, Prague, reports his recovery of comet P/2004 V3 (cf. IAUCs 8429, 8438) as an apparently stellar object on CCD images obtained on July 18 and 19 with the "F/(Ph)otometric Robotic Atmospheric Monitor" 0.3-m f/6.8 reflector located at the Pierre Auger Observatory at Malarguee, Mendoza, Argentina. His astrometry is tabulated below. 2023 UT R.A. (2000) Decl. Mag. Observer July 18.23859 23 30 14.56 -60 06 07.4 19.6 Masek 18.25445 23 30 13.62 -60 06 11.8 19.7 " 19.38317 23 29 14.32 -60 10 41.4 19.7 " 19.39082 23 29 13.87 -60 10 43.3 19.6 " 19.37394 23 29 14.80 -60 10 39.0 19.6 " 19.40007 23 29 13.37 -60 10 45.0 19.6 " 19.40776 23 29 12.97 -60 10 47.4 19.7 " H. Sato (Bunkyo-ku, Tokyo, Japan) reports pre-recovery CCD observations obtained remotely with a 0.51-m f/6.8 astrograph located at Siding Spring, NSW, Australia, on June 19 (astrometry tabulated below) in response to being alerted of Masek's recovery; eight stacked 120-s exposures show a strongly condensed coma 8" in diameter with no tail; the magnitude was measured to be 19.0 within a circular aperture of radius 4".9. 2023 UT R.A. (2000) Decl. Mag. Observer June 19.77276 23 40 02.60 -58 01 27.6 Sato 19.77886 23 40 02.64 -58 01 29.4 19.0 " The Masek observations have residuals of +0.13 deg in R.A. and +0.55 deg in Decl. from the prediction by S. Nakano on NK 1246R and in the ICQ's 2020 Comet Handbook, with a corresponding correction of Delta(T) = -3.20 days. The following linked orbital elements by Nakano are from 66 observations spanning 2004-2023 (mean residual 0".4); the uncertainty in the orbital period is now +/- 0.02 day. The comet passed 0.27 AU from Saturn in 1980 March and 1.03 AU from Jupiter in 1986 September; the comet will pass 3.30 AU from Saturn on 2038 Jan. 31 UT. Epoch = 1986 Jan. 10.0 TT T = 1985 Dec. 31.22468 TT Peri. = 324.22375 e = 0.4528650 Node = 356.30573 2000.0 q = 3.9661485 AU Incl. = 50.32629 a = 7.2489400 AU n = 0.05050011 P = 19.52 years Epoch = 2004 Nov. 11.0 TT T = 2004 Nov. 11.36102 TT Peri. = 322.36823 e = 0.4460995 Node = 356.09291 2000.0 q = 3.9382105 AU Incl. = 50.45313 a = 7.1099597 AU n = 0.05198803 P = 18.96 years Epoch = 2023 Dec. 2.0 TT T = 2023 Nov. 21.07828 TT Peri. = 322.55794 e = 0.4455121 Node = 356.12421 2000.0 q = 3.9498927 AU Incl. = 50.44575 a = 7.1234968 AU n = 0.05183991 P = 19.01 years Epoch = 2042 Oct. 3.0 TT T = 2042 Oct. 9.52358 TT Peri. = 322.42031 e = 0.4466700 Node = 356.02972 2000.0 q = 3.9298726 AU Incl. = 50.48293 a = 7.1022224 AU n = 0.05207301 P = 18.93 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, noting that the current pre-perihelion brightness is about 2.5 mag fainter than what would be predicted from the 2004-2005 observations (with H10 = 8.5), which were post-perihelion only. Monitoring the comet's total brightness at this return is encouraged. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2023 06 25 23 40.30 -58 23.2 3.521 4.042 114.0 13.3 18.8 2023 07 05 23 38.30 -59 07.9 3.436 4.030 119.1 12.7 18.7 2023 07 15 23 32.80 -59 52.6 3.364 4.019 123.8 12.1 18.7 2023 07 25 23 23.67 -60 31.0 3.308 4.009 127.6 11.6 18.6 2023 08 04 23 11.16 -60 55.4 3.269 4.000 130.2 11.2 18.6 2023 08 14 22 56.04 -60 58.8 3.250 3.991 131.2 11.0 18.6 2023 08 24 22 39.59 -60 35.1 3.252 3.983 130.5 11.1 18.6 2023 09 03 22 23.39 -59 41.8 3.275 3.976 128.0 11.5 18.6 2023 09 13 22 08.91 -58 19.8 3.319 3.970 123.9 12.1 18.6 2023 09 23 21 57.18 -56 33.0 3.384 3.965 118.7 12.8 18.6 2023 10 03 21 48.70 -54 27.2 3.466 3.960 112.6 13.5 18.7 2023 10 13 21 43.46 -52 08.2 3.564 3.956 105.9 14.0 18.7 2023 10 23 21 41.21 -49 41.2 3.676 3.953 98.9 14.4 18.8 2023 11 02 21 41.56 -47 10.4 3.796 3.951 91.6 14.5 18.9 2023 11 12 21 44.06 -44 38.7 3.924 3.950 84.3 14.4 18.9 2023 11 22 21 48.35 -42 08.1 4.054 3.950 76.9 14.1 19.0 2023 12 02 21 54.05 -39 39.9 4.185 3.950 69.6 13.5 19.1 2023 12 12 22 00.87 -37 14.7 4.313 3.952 62.3 12.7 19.1 2023 12 22 22 08.56 -34 52.8 4.435 3.954 55.0 11.8 19.2 2024 01 01 22 16.91 -32 34.5 4.548 3.957 47.9 10.6 19.3 2024 01 11 22 25.75 -30 19.6 4.651 3.961 40.9 9.4 19.3 2024 04 20 23 56.61 -10 55.3 4.809 4.044 36.4 8.5 19.5 2024 04 30 00 04.12 -09 18.1 4.730 4.057 43.3 9.8 19.5 2024 05 10 00 11.03 -07 44.6 4.636 4.070 50.6 11.0 19.4 2024 05 20 00 17.21 -06 15.2 4.529 4.084 58.0 12.1 19.4 2024 05 30 00 22.58 -04 49.8 4.411 4.099 65.7 13.0 19.3 2024 06 09 00 26.99 -03 28.6 4.284 4.114 73.6 13.7 19.3 2024 06 19 00 30.31 -02 11.8 4.150 4.130 81.8 14.1 19.3 2024 06 29 00 32.39 -00 59.5 4.014 4.147 90.4 14.2 19.2 2024 07 09 00 33.09 +00 08.1 3.878 4.165 99.3 13.9 19.1 2024 07 19 00 32.27 +01 10.6 3.746 4.183 108.6 13.3 19.1 2024 07 29 00 29.84 +02 07.8 3.623 4.201 118.3 12.3 19.0 2024 08 08 00 25.74 +02 59.4 3.514 4.221 128.5 10.8 19.0 2024 08 18 00 20.02 +03 45.0 3.423 4.240 139.1 9.0 18.9 2024 08 28 00 12.88 +04 24.6 3.356 4.261 150.0 6.8 18.9 2024 09 07 00 04.62 +04 58.2 3.316 4.282 161.1 4.4 18.9 2024 09 17 23 55.70 +05 26.2 3.307 4.303 171.2 2.0 18.9 2024 09 27 23 46.67 +05 49.6 3.331 4.325 171.8 1.9 19.0 2024 10 07 23 38.07 +06 09.7 3.387 4.348 161.8 4.1 19.0 2024 10 17 23 30.43 +06 28.4 3.474 4.371 150.8 6.4 19.1 2024 10 27 23 24.12 +06 47.5 3.589 4.395 139.7 8.4 19.2 2024 11 06 23 19.39 +07 08.6 3.727 4.418 129.0 10.0 19.3 2024 11 16 23 16.34 +07 33.2 3.884 4.443 118.6 11.3 19.4 2024 11 26 23 14.96 +08 02.4 4.055 4.468 108.6 12.1 19.5 2024 12 06 23 15.16 +08 36.8 4.234 4.493 98.9 12.5 19.7 2024 12 16 23 16.80 +09 16.9 4.417 4.519 89.6 12.6 19.8 2024 12 26 23 19.70 +10 02.8 4.599 4.545 80.7 12.3 19.9 2025 01 05 23 23.72 +10 54.5 4.777 4.571 72.1 11.8 20.0 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2023 CBAT 2023 July 27 (CBET 5282) Daniel W. E. Green