Electronic Telegram No. 4302
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/2016 P3 = P/2003 SQ_215 (NEAT-LONEOS)
[Editor's note:  This text replaces that on CBET 4301 (identifications).]
     E. Lilly and R. Wainscoat reported the discovery of a comet on four
w-band exposures taken on Aug. 12 with the 1.8-m Pan-STARRS1 telescope at
Haleakala (discovery observations tabulated below); in each image, the object
shows a broad, low-surface-brightness tail extending towards p.a. 210 degrees
for approximately 6"; the full-width-at-half-maximum of the nuclear
condensation in a co-added image is 2".5, compared to 1".8 for adjacent stars.
M. Meyer and G. V. Williams identified this comet with comet P/2003 SQ_215
(cf. IAUC 8274), and earlier CCD observations this year made by Pan-STARRS1
(July 7) and by S. Maticic with the Crni Vrh 0.6-m f/3.3 Deltagraph (Aug. 9)
were also identified.  The linkage shows this to be the second observed
apparition of this comet; the indicated correction to the prediction by G. V.
Williams on MPC 89014 is Delta(T) = -5.08 days; the indicated correction to
the prediction by S. Nakano in the ICQ's 2015 Comet Handbook is -5.64 days.

     2016 UT             R.A. (2000) Decl.       Mag.   Observer
     July  7.57545   23 15 51.39   + 2 35 42.7   21.0   Pan-STARRS1
           7.58396   23 15 51.58   + 2 35 45.5   20.9     "
           7.60119   23 15 52.00   + 2 35 51.2   20.8     "
     Aug.  9.01511   23 19 48.67   + 4 37 05.7   18.9   Maticic
           9.03045   23 19 48.53   + 4 37 06.4   19.2     "
           9.04579   23 19 48.35   + 4 37 08.0   19.7     "
           9.06113   23 19 48.09   + 4 37 09.2   18.9     "
          12.47909   23 19 01.58   + 4 41 33.4   19.9   Pan-STARRS1
          12.48961   23 19 01.33   + 4 41 34.4   20.0     "
          12.50014   23 19 01.20   + 4 41 34.9   19.9     "
          12.51072   23 19 00.99   + 4 41 35.7   19.9     "

After the comet was posted on the Minor Planet Center's NEOCP webpage, J.-F.
Soulier noted the cometary appearance on unfiltered CCD images taken on Aug.
14.01-14.06 UT with a 0.30-m f/3.8 Newtonian reflector at Maisoncelles,
France; stacked images show a 15" coma and a 13"-long tail in p.a. 195 deg,
with a red magnitude of 19.1-19.2 as measured in an aperture of radius 6".5.
Unfiltered CCD images taken by A. Maury, J.-B. de Vanssay, and J.-F. Soulier
on Aug. 14.4 with a 0.4-m f/8 Ritchey-Chretien reflector at San Pedro de
Atacama, Chile, show a 15" coma and a 21"-long tail in p.a. 210 deg; the
red magnitude was measured to be 19.0-19.1 in an aperture of radius 6".2.
     The available astrometry, the following elliptical orbital elements by
G. V. Williams, and an ephemeris appear on MPEC 2016-P122.

                    Epoch = 2017 Feb. 16.0 TT
     T = 2017 Jan. 27.72707 TT        Peri. = 137.54352
     e = 0.5835835                    Node  = 257.24352 2000.0
     q = 2.2801753 AU                 Incl. =   5.58179
       a =  5.4757083 AU   n = 0.07692077   P =  12.81 years


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

                         (C) Copyright 2016 CBAT
2016 August 15                   (CBET 4302)              Daniel W. E. Green