Electronic Telegram No. 5409 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 L4 (RANKIN) David Rankin, Lunar and Planetary Laboratory, University of Arizona, reports his discovery of another comet on images taken on June 15 (discovery observations tabulated below) with the Mt. Lemmon Survey's 1.5-m reflector, noting the object to have an apparent 6" coma. 2024 UT R.A. (2000) Decl. Mag. Observer June 15.42612 22 43 42.20 + 6 31 23.5 20.9 Rankin 15.43133 22 43 41.69 + 6 31 16.6 20.8 " 15.43656 22 43 41.13 + 6 31 09.9 " 15.44754 22 43 40.14 + 6 30 54.7 20.9 " 15.44955 22 43 39.93 + 6 30 51.7 21.1 " 15.45080 22 43 39.83 + 6 30 50.5 20.7 " G. J. Leonard reported that CCD images obtained with the 1-m reflector of Steward Observatory at Mt. Lemmon on June 16.5 UT showed a condensed coma of size about 8" in twelve 42-s exposures, with no tail. The available astrometry appears on MPEC 2024-N106. The following two-body orbital elements by S. Nakano (Central Bureau) are from 67 observations spanning 2024 June 15-July 8 (mean residual 0".3). There are no close appraoches to major planets, and a search through archival astrometry records revealed no objects that could be this comet. T = 2024 Apr. 14.28890 TT Peri. = 53.70583 e = 0.6987753 Node = 139.77119 2000.0 q = 0.6719164 AU Incl. = 10.05830 a = 2.2306151 AU n = 0.29584697 P = 3.33 years P. Jenniskens writes that a possible associated meteor shower is the delta1 Canis Minorids (cf. Jenniskens 2024, *Atlas of Earth's Meteor Showers*, p. 663). Noting the unusally small orbit of this comet, S. Deen writes that he searched 1.2-m Schmidt Palomar telescope ("Zwicky Transient Facility") images of the comet's field from 2024 May 3-9 and found nothing down to magnitude V = 21.0. The following ephemeris by the undersigned from the above orbital elements uses photometric power-law parameters H = 20.5 and 2.5n = 10.0 for the magnitudes, which indicate that this is a very small comet. There was likely an outburst around the time of discovery. Additional observations are encouraged for this unusual object before it fades in August. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2024 06 14 22 45.82 +07 03.6 0.480 1.177 97.2 58.9 19.6 2024 06 19 22 38.06 +05 09.7 0.489 1.233 104.4 53.0 19.9 2024 06 24 22 29.40 +03 10.8 0.499 1.289 111.9 47.0 20.1 2024 06 29 22 19.76 +01 06.1 0.510 1.344 119.6 41.1 20.3 2024 07 04 22 09.20 -01 04.0 0.522 1.398 127.7 35.1 20.5 2024 07 09 21 57.86 -03 17.6 0.538 1.452 135.9 29.2 20.8 2024 07 14 21 46.03 -05 32.0 0.559 1.505 144.2 23.3 21.0 2024 07 19 21 34.06 -07 43.5 0.584 1.558 152.5 17.5 21.3 2024 07 24 21 22.33 -09 48.5 0.615 1.609 160.7 12.1 21.5 2024 07 29 21 11.17 -11 44.2 0.653 1.660 168.6 7.0 21.8 2024 08 03 21 00.88 -13 28.4 0.697 1.710 175.5 2.6 22.0 2024 08 08 20 51.70 -15 00.0 0.747 1.759 174.9 2.9 22.3 2024 08 13 20 43.79 -16 18.9 0.803 1.807 168.5 6.4 22.6 2024 08 18 20 37.22 -17 25.5 0.866 1.855 161.9 9.7 22.9 2024 08 23 20 31.98 -18 20.9 0.933 1.901 155.7 12.6 23.1 2024 08 28 20 28.01 -19 06.2 1.006 1.947 149.8 15.1 23.4 2024 09 02 20 25.25 -19 42.6 1.084 1.992 144.2 17.2 23.7 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2024 CBAT 2024 July 9 (CBET 5409) Daniel W. E. Green