Electronic Telegram No. 5411
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 N2 = P/2010 T8 = P/2017 R2 (PANSTARRS)
R. Weryk, Department of Physics and Astronomy, University of Western
Ontario, reports the discovery of another comet in images obtained with the
Pan-STARRS1 1.8-m Ritchey-Chretien reflector at Haleakala on 2024 July 3; the
discovery observations are tabulated below along with additional observations
taken earlier this year with the Pan-STARRS2 1.8-m Ritchey-Chretien reflector
at Haleakala and identified by Weryk (the June observations were already in
the Minor Planet Center's "isolated tracklet file"). Four 45-s w-band survey
images taken on 2024 July 3 in 1".4-1".6 seeing show a very condensed head
of size 1".7 (full-width-at-half-maximum) with a straight 5" tail toward
p.a. 245 degrees. The April 9 observations were found later by Weryk.
2024 UT R.A. (2000) Decl. Mag. Observer
Apr. 9.61330 20 12 15.19 -15 34 50.7 22.6 Pan-STARRS2
9.61851 20 12 15.64 -15 34 48.2 22.1 "
June 7.57144 21 08 30.46 - 7 43 09.5 21.7 "
7.57932 21 08 30.62 - 7 43 06.4 22.0 "
7.59507 21 08 30.92 - 7 42 59.9 21.8 "
15.53828 21 10 30.49 - 6 52 14.5 21.5 "
15.55089 21 10 30.58 - 6 52 09.9 21.4 "
15.56354 21 10 30.68 - 6 52 05.5 21.5 "
July 3.52308 21 09 13.86 - 5 25 40.9 21.1 Pan-STARRS1
3.53454 21 09 13.63 - 5 25 38.6 21.1 "
3.54594 21 09 13.41 - 5 25 36.3 20.9 "
3.55735 21 09 13.18 - 5 25 33.8 21.5 "
Three 60-s gri-band follow-up images taken by Weryk (and R. Wainscoat) on July
4.6 UT with the 3.6-m Canada-France-Hawaii Telescope (queue observer H.
Januszewski; queue coordinator V. Khatu) in 1".0 seeing show a very condensed
head of size 1".2 (FWHM) and a straight 10" tail in p.a. 240 degrees. Weyrk
subsequently identified previous apparently asteroidal images of this comet in
Pan-STARRS1 exposures from 2010 Oct. 8, 2016 June 29, and 2017 Sept. 2,
together with additional Pan-STARRS2 images from 2023 Mar. 26 and 27 (as
tabulated below).
2010 UT R.A. (2000) Decl. Mag. Observer
Oct. 8.41151 2 19 04.05 +20 01 45.2 23.3 Pan-STARRS1
8.41360 2 19 03.95 +20 01 44.1 22.1 "
8.43186 2 19 03.27 +20 01 40.2 23.8 "
8.45092 2 19 02.50 +20 01 36.1 23.8 "
2016 UT R.A. (2000) Decl. Mag. Observer
June 29.28446 14 45 32.36 -16 41 18.1 22.5 Pan-STARRS1
29.29686 14 45 32.39 -16 41 16.1 21.8 "
29.30916 14 45 32.40 -16 41 13.9 22.7 "
29.32144 14 45 32.44 -16 41 11.8 22.2 "
2017 UT R.A. (2000) Decl. Mag. Observer
Sept. 2.41602 0 17 22.76 +13 15 55.7 22.4 Pan-STARRS1
2.42709 0 17 22.34 +13 15 53.5 21.5 "
2.43818 0 17 22.00 +13 15 51.8 22.3 "
2023 UT R.A. (2000) Decl. Mag. Observer
Mar. 26.47100 12 59 02.39 -15 13 41.6 23.6 Pan-STARRS2
27.42239 12 58 25.26 -15 09 45.1 23.2 "
S. Deen (Simi Valley, CA, USA) writes that he has identified observations
of this comet in publicly available CCD images from 2009 and 2017, as
tabulated below. The 2017 observations are from DECam images taken at the 4-m
reflector at Cerro Tololo Interamerican Observatory. The 200s g-band image
from 2017 July 23 shows an essentially stellar nuclear condensation of size
about 0".8 (FWHM), the same as surrounding stars, but with a seemingly
partially disconnected faint, broad tail extending 10" from the condensation
in p.a. 255 degrees. The 2017 July 19 z-band image shows the comet again with
an apparently stellar (and very faint) nuclear condensation but with a 12"
tail in p.a. 257 degrees. The Pan-STARRS1 r-band images from 2009 are too
faint to be able to make out any details.
2009 UT R.A. (2000) Decl. Mag. Observer
June 27.46784 19 35 28.88 -13 09 54.9 Pan-STARRS1
27.48024 19 35 28.42 -13 09 52.7 21.1 "
2017 UT R.A. (2000) Decl. Mag. Observer
July 19.41577 0 22 02.61 +12 19 49.1 DECam
23.39497 0 23 23.45 +12 38 17.3 23.5 "
Additional available astrometry for this comet appears on MPEC 2024-N123.
The following linked elliptical orbital elements by S. Nakano (Central Bureau)
are from 35 observations spanning 2009 June 27-2024 July 9 (mean residual
0".3). The comet passed 0.23 AU from Jupiter on 1989 Nov. 4 and will pass
0.85 AU from Jupiter on 2049 Jan. 20 UT; the 2049 passage will increase the
orbital period to 8.0 yr, with the perihelion distance moving out to q = 2.73.
Nakano's computations indicate that the comet previously had orbital elements
T = 1913 May 14, q = 4.290 AU, e = 0.062, Peri. = 24.1 deg, Node = 282.5 deg,
i = 13.1 deg (equinox J2000.0), a = 4.576 AU, P = 9.79 years.
Epoch = 1994 June 17.0 TT
T = 1994 July 5.08186 TT Peri. = 48.07454
e = 0.3487920 Node = 245.99366 2000.0
q = 2.4966385 AU Incl. = 7.78051
a = 3.8338571 AU n = 0.13129560 P = 7.51 years
Epoch = 2002 Jan. 6.0 TT
T = 2002 Jan. 13.59174 TT Peri. = 48.20307
e = 0.3471843 Node = 245.90766 2000.0
q = 2.5099879 AU Incl. = 7.77136
a = 3.8448644 AU n = 0.13073219 P = 7.54 years
Epoch = 2009 July 28.0 TT
T = 2009 July 23.18056 TT Peri. = 48.23299
e = 0.3489598 Node = 245.83919 2000.0
q = 2.4993989 AU Incl. = 7.77159
a = 3.8390853 AU n = 0.13102749 P = 7.52 years
Epoch = 2017 Jan. 7.0 TT
T = 2017 Jan. 1.52308 TT Peri. = 48.58539
e = 0.3574490 Node = 245.15055 2000.0
q = 2.4384660 AU Incl. = 7.79164
a = 3.7949767 AU n = 0.13331850 P = 7.39 years
Epoch = 2024 June 19.0 TT
T = 2024 May 31.05837 TT Peri. = 48.88492
e = 0.3571240 Node = 245.04642 2000.0
q = 2.4403745 AU Incl. = 7.78981
a = 3.7960268 AU n = 0.13326318 P = 7.40 years
Epoch = 2031 Oct. 21.0 TT
T = 2031 Oct. 18.60421 TT Peri. = 48.42223
e = 0.3558314 Node = 245.00450 2000.0
q = 2.4496088 AU Incl. = 7.78362
a = 3.8027449 AU n = 0.13291019 P = 7.42 years
Epoch = 2039 Apr. 2.0 TT
T = 2039 Mar. 18.10616 TT Peri. = 48.42908
e = 0.3538584 Node = 244.91440 2000.0
q = 2.4608856 AU Incl. = 7.77034
a = 3.8085858 AU n = 0.13260456 P = 7.43 years
Epoch = 2046 Aug. 3.0 TT
T = 2046 Aug. 22.11243 TT Peri. = 48.63029
e = 0.3552758 Node = 244.85536 2000.0
q = 2.4499486 AU Incl. = 7.77771
a = 3.7999950 AU n = 0.13305449 P = 7.41 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 06 19 21 10.88 -06 32.2 1.672 2.444 129.1 18.8 20.5
2024 06 29 21 10.30 -05 43.2 1.595 2.448 138.1 16.1 20.4
2024 07 09 21 07.32 -05 08.8 1.534 2.454 147.6 12.8 20.3
2024 07 19 21 02.35 -04 50.7 1.494 2.461 157.0 9.3 20.3
2024 07 29 20 56.06 -04 48.9 1.476 2.471 165.0 6.1 20.3
2024 08 08 20 49.32 -05 01.9 1.482 2.482 167.5 5.1 20.3
2024 08 18 20 43.14 -05 26.1 1.513 2.494 161.8 7.3 20.4
2024 08 28 20 38.40 -05 56.8 1.567 2.509 152.9 10.6 20.5
2024 09 07 20 35.71 -06 29.5 1.643 2.524 143.4 13.8 20.6
2024 09 17 20 35.46 -06 59.7 1.738 2.542 134.1 16.5 20.8
2024 09 27 20 37.68 -07 24.2 1.849 2.560 125.1 18.7 20.9
2024 10 07 20 42.26 -07 40.8 1.973 2.580 116.6 20.3 21.1
2024 10 17 20 48.99 -07 47.8 2.108 2.601 108.5 21.3 21.3
2024 10 27 20 57.55 -07 44.8 2.250 2.623 100.7 21.9 21.4
2024 11 06 21 07.67 -07 31.4 2.397 2.647 93.3 22.0 21.6
2024 11 16 21 19.06 -07 07.6 2.548 2.671 86.2 21.7 21.8
2024 11 26 21 31.47 -06 33.9 2.700 2.697 79.3 21.1 22.0
2024 12 06 21 44.68 -05 50.9 2.851 2.723 72.6 20.2 22.1
2024 12 16 21 58.51 -04 59.3 3.000 2.750 66.0 19.1 22.3
2024 12 26 22 12.79 -04 00.0 3.144 2.779 59.6 17.8 22.4
2025 01 05 22 27.41 -02 53.8 3.283 2.807 53.2 16.3 22.6
NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.
(C) Copyright 2024 CBAT
2024 July 10 (CBET 5411) Daniel W. E. Green