Electronic Telegram No. 5356 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/2024 C5 = P/2012 WA_34 (LEMMON-PANSTARRS) E. Schwab, Egelsbach, Germany, reports the recovery of comet P/2012 WA_34 (cf. CBET 3379) on ten 600-s CCD exposures taken on Feb. 13.0 UT through a collaboration with F. Ocana, D. Abreu, M. Busch, L. Conversi, R. Kresken, and M. Micheli using the 1.0-m f/4.4 reflector, noting only that no tail was visible. Confirming observations with the same telescope on Feb. 14.0, taken in 3".5 seeing, show a small coma of size 5".3 (full-width-at-half-maximum) in ten 60-s stacked exposures. The astrometry is tabulated below. 2024 UT R.A. (2000) Decl. Mag. Observer Feb. 12.97344 8 57 57.15 +23 02 11.9 20.2 Schwab 12.97796 8 57 56.99 +23 02 12.2 20.5 " 12.98402 8 57 56.77 +23 02 13.3 20.5 " 12.98931 8 57 56.54 +23 02 14.3 20.3 " 14.00707 8 57 17.81 +23 05 34.0 20.6 " 14.01499 8 57 17.47 +23 05 35.9 20.4 " 14.02289 8 57 17.18 +23 05 36.2 20.8 " S. Deen (Simi Valley, CA, USA) writes that, as a result of the Minor Planet Center posting this recovery pre-publication on their new webpage (URL https://www.minorplanetcenter.net/iau/recovery/recovery.html), he searched for additional observations in publicly available online data, from which he found single-image observations obtained with the Cerro Tololo 4-m reflector (+ DECam) on 2022 Sept. 18 and 19. Deen notes that the comet was very faint (mag 21.6-22.0) and essentially stellar in appearance. His astrometry appears on MPEC 2024-D103. The residuals of Schwab's recovery observations are +145" in R.A. and -30" in Decl. from the prediction in NK 2406 (and the ICQ's 2023 Comet Handbook), with a correponding correction of Delta(T) = -0.16 day. The following linked orbital elements by S. Nakano (Central Bureau) are from 39 observations spanning 2011 Sept. 26-2024 Feb. 14 (mean residual 0".4). There are no close approaches to major planets. Epoch = 2013 Jan. 28.0 TT T = 2013 Jan. 24.74500 TT Peri. = 353.15904 e = 0.3396577 Node = 94.52353 2000.0 q = 3.1734284 AU Incl. = 6.11884 a = 4.8057323 AU n = 0.09355451 P = 10.54 years Epoch = 2023 June 25.0 TT T = 2023 July 8.64003 TT Peri. = 356.63762 e = 0.3434109 Node = 93.55606 2000.0 q = 3.0714282 AU Incl. = 6.08283 a = 4.6778545 AU n = 0.09741683 P = 10.12 years Epoch = 2033 Aug. 31.0 TT T = 2033 Aug. 30.70410 TT Peri. = 356.68840 e = 0.3426126 Node = 93.56254 2000.0 q = 3.0899997 AU Incl. = 6.07571 a = 4.7004244 AU n = 0.09671603 P = 10.19 years Epoch = 2043 Nov. 7.0 TT T = 2043 Nov. 26.19701 TT Peri. = 356.74452 e = 0.3414067 Node = 93.49090 2000.0 q = 3.1113031 AU Incl. = 6.06787 a = 4.7241643 AU n = 0.09598792 P = 10.27 years The following ephemeris by the undersigned from the above orbital elements uses photometric power-law parameters H = 12.5 and 2.5n = 10 for the magnitudes. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2024 01 11 09 18.75 +20 43.2 2.336 3.248 153.8 7.7 19.5 2024 01 21 09 13.17 +21 28.2 2.306 3.266 165.0 4.5 19.5 2024 01 31 09 06.63 +22 12.5 2.304 3.285 174.1 1.8 19.5 2024 02 10 08 59.88 +22 51.9 2.331 3.305 169.0 3.3 19.5 2024 02 20 08 53.72 +23 23.1 2.387 3.325 158.1 6.4 19.6 2024 03 01 08 48.83 +23 44.2 2.470 3.346 147.2 9.2 19.7 2024 03 11 08 45.68 +23 54.5 2.577 3.368 136.6 11.7 19.8 2024 03 21 08 44.53 +23 54.5 2.703 3.390 126.4 13.7 20.0 2024 03 31 08 45.43 +23 45.1 2.843 3.413 116.8 15.1 20.1 2024 04 10 08 48.27 +23 27.4 2.996 3.436 107.8 16.1 20.2 2024 04 20 08 52.88 +23 02.2 3.155 3.460 99.2 16.7 20.4 2024 04 30 08 59.03 +22 30.4 3.319 3.485 91.0 16.8 20.5 2024 05 10 09 06.48 +21 52.7 3.484 3.509 83.1 16.6 20.7 2024 05 20 09 15.02 +21 09.5 3.647 3.534 75.6 16.1 20.8 2024 05 30 09 24.44 +20 21.4 3.806 3.560 68.4 15.4 20.9 2024 06 09 09 34.55 +19 28.9 3.959 3.586 61.4 14.4 21.0 2024 06 19 09 45.23 +18 32.2 4.105 3.612 54.6 13.3 21.1 2024 06 29 09 56.31 +17 32.0 4.241 3.639 47.9 12.0 21.2 2024 07 09 10 07.71 +16 28.7 4.367 3.666 41.4 10.6 21.3 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2024 CBAT 2024 February 22 (CBET 5356) Daniel W. E. Green