[Iaude] CBET 5379: COMET P/2024 F1

[quai at eps.harvard.edu]

                                                  Electronic Telegram No. 5379
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau at eps.harvard.edu (alternate cbat at iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


COMET P/2024 F1 (PANSTARRS)
     R. Weryk, Department of Physics and Astronomy, University of Western
Ontario, reports the discovery of another comet in four 45-s w-band survey
images obtained in 1".2-1".4 seeing with the Pan-STARRS1 1.8-m reflector at
Haleakala on Mar. 18 (discovery observations tabulated below).  The very
condensed coma showed a size of 1".8 (full-width-at-half-maximum) in stacked
images, and there was a clear 8" tail in p.a. 305 degrees.

     2024 UT             R.A. (2000) Decl.       Mag.
     Mar. 18.41096   11 56 42.07   -12 37 58.8   20.7
          18.42262   11 56 41.51   -12 37 54.3   20.9
          18.43427   11 56 40.95   -12 37 49.7   20.6
          18.44593   11 56 40.41   -12 37 45.2   21.3
          18.52141   11 56 36.81   -12 37 14.5   21.0
          18.52222   11 56 36.78   -12 37 14.2   21.1

Weryk adds that four additional stacked 45-s Pan-STARRS1 w-band survey images
taken in 1".3-1".4 seeing on Mar. 30.33-30.37 UT show a condensed coma of size
1".8 (FWHM) and a straight 6" tail in p.a. 305 degrees.  He further notes that
images from Feb. 15 show the comet with a clear 8" tail in p.a. 300 degrees,
but he was unable to measure astrometry because the comet's head was lost in
a "cell gap" on the camera chip.  Weryk further adds that three 60-s gri-band
follow-up images were obtained via R. Wainscoat with the 3.6-m Canada-France-
Hawaii Telescope at Mauna Kea in 1".0 seeing on Apr. 5.47 (queue oberver L.
Wells; queue coordinator T. Burdullis, which show this clearly to be a comet
in the best image, with a very condensed coma of size 1".4 (FWHM) and a 9"
tail in p.a. 305 degrees.
     After the comet was posted on the Minor Planet Center's PCCP webpage,
H. Sato (Bunkyo-ku, Tokyo, Japan) obtained ten stacked 120-s CCD exposures
remotely on Mar. 18.56-18.57 UT with a 0.51-m f/6.8 astrograph located at
Siding Spring, NSW, Australia, showing a strongly condensed coma 6" in
diameter with no tail; the magnitude was 20.6 as measured within a circular
aperture of radius 3".2.
     The available astrometry appears on MPEC 2024-G102.  The following
elliptical orbital elements by S. Nakano (Central Bureau) are from 40
observations spanning 2024 Mar. 18-Apr. 6.  The comet passed 0.62 AU from
Jupiter on 2021 Feb. 17 UT.

     T = 2023 Oct. 25.67633 TT        Peri. = 229.53400
     e = 0.4597310                    Node  = 251.55325 2000.0
     q = 1.8594016 AU                 Incl. =   7.00390
       a =  3.4416217 AU   n = 0.15436875   P =   6.38 years

The following ephemeris by the undersigned from the above orbital elements
uses photometric power-law parameters H = 15.5 and 2.5n = 10 for the
magnitudes.

Date    TT    R. A. (2000) Decl.     Delta      r     Elong.  Phase  Mag.
2024 03 31    11 47.91   -11 04.9    1.282    2.263   165.7     6.3  19.6
2024 04 10    11 42.67   -09 47.5    1.351    2.307   157.1     9.7  19.8
2024 04 20    11 39.75   -08 37.3    1.443    2.352   147.4    13.3  20.0
2024 04 30    11 39.36   -07 40.8    1.554    2.397   137.7    16.4  20.3
2024 05 10    11 41.44   -07 00.8    1.683    2.444   128.6    18.8  20.5
2024 05 20    11 45.76   -06 38.4    1.826    2.491   120.0    20.6  20.8
2024 05 30    11 51.99   -06 32.4    1.980    2.538   111.9    21.8  21.0
2024 06 09    11 59.81   -06 41.1    2.142    2.585   104.2    22.4  21.3
2024 06 19    12 08.95   -07 02.8    2.310    2.633    96.9    22.5  21.5
2024 06 29    12 19.15   -07 35.1    2.481    2.681    90.0    22.3  21.8
2024 07 09    12 30.21   -08 16.2    2.655    2.729    83.3    21.7  22.0
2024 07 19    12 41.97   -09 04.4    2.828    2.777    76.7    20.9  22.2
2024 07 29    12 54.30   -09 58.0    3.000    2.825    70.4    19.8  22.4
2024 08 08    13 07.11   -10 55.6    3.168    2.873    64.1    18.5  22.6
2024 08 18    13 20.31   -11 55.9    3.330    2.920    57.9    17.1  22.8
2024 08 28    13 33.83   -12 57.9    3.486    2.968    51.7    15.5  22.9
2024 09 07    13 47.63   -14 00.4    3.634    3.015    45.5    13.8  23.1


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2024 CBAT
2024 April 9                     (CBET 5379)              Daniel W. E. Green