Electronic Telegram No. 5480
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/2024 X1 (FAZEKAS)
Jacqueline B. Fazekas, Lunar and Planetary Laboratory, University of
Arizona, reports her discovery of a comet on CCD images obtained with the Mt.
Lemmon Survey's 1.5-m reflector in Arizona on Dec. 11 (discovery observations
tabulated below); she described the comet as having a very condensed coma of
size 10"-12" with no tail in four 30-s exposures taken in 2".3-2".5 seeing.
2024 UT R.A. (2000) Decl. Mag. Observer
Dec. 11.21795 5 08 59.25 +31 24 19.6 19.3 Fazekas
11.22826 5 08 58.86 +31 24 19.7 19.9 "
11.23341 5 08 58.67 +31 24 19.3 19.3 "
11.27728 5 08 57.00 +31 24 17.6 19.4 "
11.39303 5 08 52.65 +31 24 14.0 20.2 "
11.40766 5 08 52.12 +31 24 13.5 20.0 "
11.42247 5 08 51.55 +31 24 13.1 20.0 "
After the comet was posted on the Minor Planet Center's PCCP webpage, R.
Weryk (Department of Physics and Astronomy, University of Western Ontario)
reported that three 45-s i-band survey images taken on Dec. 19.5 UT with the
Pan-STARRS1 1.8-m Ritchey-Chretien reflector at Haleakala, HI, USA, in 1".2-
1".3 seeing show a condensed head of size 1".9 with no obvious tail.
The available astrometry appears on MPEC 2024-Y20. The following
preliminary orbital elements by S. Nakano (Central Bureau) are from 41
observations spanning Dec. 11-19 (mean residual 0".4). There were apparently
some close approaches to Jupiter and Saturn in the past, and the orbital
period is uncertain by at least 1-2 years.
T = 2025 July 26.25788 TT Peri. = 123.24304
e = 0.6103846 Node = 352.44160 2000.0
q = 3.7858563 AU Incl. = 6.43433
a = 9.7169055 AU n = 0.03253959 P = 30.3 years
The following ephemeris by the undersigned from the above orbital elements
uses photometric power-law parameters H = 12.0 and 2.5n = 8 for the
magnitudes.
Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag.
2024 12 16 05 06.08 +31 21.0 3.107 4.079 169.8 2.5 19.3
2024 12 26 05 00.29 +31 10.1 3.113 4.055 160.9 4.6 19.3
2025 01 05 04 55.38 +30 54.9 3.147 4.031 150.4 6.9 19.3
2025 01 15 04 51.87 +30 37.3 3.206 4.009 139.8 9.1 19.4
2025 01 25 04 50.09 +30 19.3 3.288 3.987 129.5 11.0 19.4
2025 02 04 04 50.23 +30 02.3 3.387 3.966 119.5 12.5 19.4
2025 02 14 04 52.32 +29 47.5 3.500 3.946 109.9 13.6 19.5
2025 02 24 04 56.29 +29 35.2 3.621 3.928 100.7 14.3 19.5
2025 03 06 05 02.03 +29 25.4 3.748 3.910 92.0 14.7 19.6
2025 03 16 05 09.37 +29 17.6 3.876 3.894 83.7 14.7 19.7
2025 03 26 05 18.12 +29 11.0 4.003 3.878 75.7 14.4 19.7
2025 04 05 05 28.13 +29 04.8 4.126 3.864 68.0 13.9 19.8
2025 04 15 05 39.19 +28 58.0 4.242 3.851 60.7 13.1 19.8
2025 04 25 05 51.17 +28 49.8 4.350 3.839 53.6 12.2 19.9
2025 05 05 06 03.91 +28 39.3 4.449 3.828 46.7 11.0 19.9
NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.
(C) Copyright 2024 CBAT
2024 December 21 (CBET 5480) Daniel W. E. Green