Electronic Telegram No. 5463
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 RU_145 = P/2016 A2 (CHRISTENSEN)
An apparently asteroidal object discovered on CCD images obatined with
the Mt. Lemmon Survey 1.5-m reflector in Arizona on Sept. 8 UT, and given the
minor-planet designation 2024 RU_145 on MPEC 2024-T198 (issued on Oct. 14),
has been identified by P. VanWylen and J. Maikner as being an accidental
recovery of comet P/2016 A2 (cf. CBET 4233). The Mt. Lemmon discovery/
recovery positions are tabulated below, with additional astrometry appearing
on MPEC 2024-U34.
2024 UT R.A. (2000) Decl. Mag.
Sept. 8.29541 23 55 09.16 +35 42 02.4 21.0
8.30118 23 55 08.87 +35 42 03.4 20.4
8.30693 23 55 08.65 +35 42 04.1 20.7
8.31269 23 55 08.42 +35 42 04.7 21.1
30.23257 23 39 30.34 +35 31 19.7 21.0
30.23793 23 39 30.14 +35 31 19.0 20.6
30.24329 23 39 29.88 +35 31 17.8 21.1
30.24864 23 39 29.63 +35 31 16.7 20.8
S. Nakano (Central Bureau) writes that T. Kobayashi (Oizumi, Gunma-ken, Japan)
has identified this comet in observations obtained (and reported with
preliminary designation P10hax1) on 2014 Dec. 27 with the Pan-STARRS1 1.8-m
Ritchey-Chretien reflector at Haleakala, Hawaii, in the Minor Planet Center's
"isolated tracklet file" (which is accessible publicly), as tabulated below.
2014 UT R.A. (2000) Decl. Mag.
Dec. 27.23394 0 52 55.83 +36 55 32.6 20.6
27.24622 0 52 56.23 +36 55 28.3 20.6
27.25852 0 52 56.65 +36 55 23.6 20.7
The residuals for the 2024 RU_145 observations are +1.30 deg in R.A. and +0.58
deg in Decl. from the prediction (15-day arc only) in NK 5033 and in the ICQ's
2024 Comet Handbook, with corresponding correction Delta(T) = -2.67 days. The
following linked orbital elements by Nakano are from 65 observations spanning
2014 Dec. 27-2024 Oct. 3 (mean residual 0".6). There are no close approaches
to any major planets after 1950.
Epoch = 2005 Mar. 11.0 TT
T = 2005 Feb. 22.51433 TT Peri. = 141.06061
e = 0.2737490 Node = 291.83614 2000.0
q = 3.4569949 AU Incl. = 26.32846
a = 4.7600551 AU n = 0.09490435 P = 10.38 years
Epoch = 2015 June 27.0 TT
T = 2015 June 26.00242 TT Peri. = 141.06082
e = 0.2748442 Node = 291.81136 2000.0
q = 3.4323713 AU Incl. = 26.37371
a = 4.7332882 AU n = 0.09571052 P = 10.30 years
Epoch = 2025 Oct. 12.0 TT
T = 2025 Oct. 22.38369 TT Peri. = 141.34425
e = 0.2731075 Node = 291.61391 2000.0
q = 3.4597688 AU Incl. = 26.35620
a = 4.7596708 AU n = 0.09491584 P = 10.38 years
Epoch = 2036 Jan. 28.0 TT
T = 2036 Jan. 25.00736 TT Peri. = 135.76617
e = 0.2676024 Node = 289.89300 2000.0
q = 3.5677445 AU Incl. = 26.35324
a = 4.8713220 AU n = 0.09167139 P = 10.75 years
Epoch = 2046 Sept.12.0 TT
T = 2046 Sept.12.04385 TT Peri. = 137.34422
e = 0.2711848 Node = 289.62336 2000.0
q = 3.4816235 AU Incl. = 26.49489
a = 4.7771008 AU n = 0.09439684 P = 10.44 years
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.
2024 09 27 23 41.83 +35 39.2 3.038 3.903 145.1 8.4 20.1
2024 10 07 23 34.84 +35 08.4 3.018 3.883 145.5 8.4 20.1
2024 10 17 23 28.80 +34 20.7 3.022 3.864 142.9 8.9 20.1
2024 10 27 23 24.24 +33 21.2 3.050 3.845 137.9 10.0 20.1
2024 11 06 23 21.52 +32 15.4 3.099 3.826 131.3 11.2 20.1
2024 11 16 23 20.83 +31 09.1 3.168 3.808 123.8 12.5 20.1
2024 11 26 23 22.18 +30 07.1 3.252 3.790 116.0 13.5 20.2
2024 12 06 23 25.50 +29 13.0 3.349 3.772 108.0 14.4 20.2
2024 12 16 23 30.64 +28 29.6 3.455 3.754 100.1 15.0 20.3
2024 12 26 23 37.41 +27 58.0 3.567 3.737 92.3 15.2 20.3
2025 01 05 23 45.61 +27 38.9 3.681 3.721 84.7 15.3 20.4
2025 01 15 23 55.07 +27 32.0 3.794 3.704 77.3 15.0 20.4
2025 01 25 00 05.62 +27 36.6 3.904 3.688 70.2 14.5 20.5
2025 02 04 00 17.11 +27 51.7 4.010 3.673 63.2 13.9 20.5
2025 02 14 00 29.43 +28 16.3 4.107 3.658 56.6 13.0 20.6
2025 07 24 04 38.12 +40 19.6 4.055 3.487 49.9 12.9 20.4
2025 08 03 04 53.16 +40 46.0 3.948 3.481 55.9 14.0 20.3
2025 08 13 05 07.44 +41 08.8 3.832 3.476 62.1 14.9 20.2
2025 08 23 05 20.77 +41 28.5 3.709 3.472 68.7 15.7 20.2
2025 09 02 05 32.91 +41 45.6 3.579 3.468 75.6 16.4 20.1
2025 09 12 05 43.65 +42 00.5 3.445 3.465 82.7 16.7 20.0
2025 09 22 05 52.72 +42 13.6 3.309 3.463 90.3 16.9 19.9
2025 10 02 05 59.82 +42 25.1 3.173 3.461 98.3 16.6 19.8
2025 10 12 06 04.69 +42 34.7 3.039 3.460 106.6 16.0 19.7
2025 10 22 06 07.07 +42 41.6 2.913 3.460 115.5 15.1 19.6
2025 11 01 06 06.76 +42 43.9 2.797 3.460 124.7 13.6 19.5
2025 11 11 06 03.73 +42 39.2 2.696 3.461 134.4 11.8 19.5
2025 11 21 05 58.15 +42 24.3 2.614 3.463 144.1 9.6 19.4
2025 12 01 05 50.49 +41 56.0 2.555 3.465 153.4 7.3 19.4
2025 12 11 05 41.55 +41 11.9 2.523 3.468 160.7 5.4 19.3
2025 12 21 05 32.27 +40 12.1 2.521 3.472 162.5 4.9 19.3
2025 12 31 05 23.71 +38 58.9 2.548 3.476 157.3 6.3 19.4
2026 01 10 05 16.73 +37 36.5 2.604 3.481 148.6 8.5 19.4
2026 01 20 05 11.87 +36 10.3 2.686 3.487 138.7 10.7 19.5
2026 01 30 05 09.45 +34 45.0 2.792 3.493 128.7 12.7 19.6
2026 02 09 05 09.47 +33 24.2 2.915 3.500 118.9 14.3 19.7
2026 02 19 05 11.78 +32 09.8 3.052 3.507 109.4 15.4 19.8
2026 03 01 05 16.17 +31 02.5 3.199 3.516 100.4 16.1 19.9
2026 03 11 05 22.35 +30 01.9 3.352 3.524 91.7 16.4 20.0
2026 03 21 05 30.07 +29 07.0 3.506 3.534 83.4 16.3 20.1
2026 03 31 05 39.07 +28 16.6 3.659 3.544 75.5 15.8 20.2
2026 04 10 05 49.13 +27 29.2 3.808 3.554 67.9 15.1 20.3
2026 04 20 06 00.05 +26 43.6 3.951 3.565 60.5 14.2 20.4
2026 04 30 06 11.64 +25 58.6 4.086 3.577 53.4 13.1 20.5
NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.
(C) Copyright 2024 CBAT
2024 October 23 (CBET 5463) Daniel W. E. Green