Electronic Telegram No. 4060
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; 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/2015 A3 (PANSTARRS)
     R. Wainscoat and M. Micheli report that an apparently asteroidal object
discovered with the 1.8-m Pan-STARRS1 telescope at Haleakala on Jan. 8 and 10
(discovery observations tabulated below) has been found to show cometary
appearance on three 60-s r-band exposures taken with the Canada-France-Hawaii
Telescope at Mauna Kea on Jan. 18.3 UT (queue observer P. Forshay).  The CFHT
exposures were tracked using the predicted motion of the object, and the
comet's image has a FWHM of 0".8, compared to 0".7 for adjacent stars (mag
21.4-21.6), but also a short, very weak tail extending approximately 5"
toward p.a. approximately 75 degrees.  Their additional CFHT images taken on
Jan. 19.2 support the cometary nature of the object, displaying a weak tail
about 5" long to the east-northeast.

     2015 UT             R.A. (2000) Decl.       Mag.
     Jan.  8.22352    1 41 23.53   + 4 42 40.9   21.0
           8.23592    1 41 19.21   + 4 42 18.3   20.9
           8.26072    1 41 10.60   + 4 41 33.8   20.7
          10.22034    1 30 47.36   + 3 46 38.3   21.5
          10.23206    1 30 43.82   + 3 46 19.7   21.5
          10.24367    1 30 40.40   + 3 46 01.8   21.4
          10.25525    1 30 36.93   + 3 45 43.6   21.5

After the object was posted on the Minor Planet Center's PCCP webpage, W. H.
Ryan reported that his R-band CCD images taken with the Magdalena Ridge
Observatory 2.4-m f/8.9 reflector on Jan. 24.1 UT yield mag 20.6-20.8 and
show a faint tail toward p.a. about 45 deg.
     The available astrometry, the following elliptical orbital elements by
G. V. Williams, and an ephemeris appear on MPEC 2015-B134.

                    Epoch = 2015 Feb. 27.0 TT
     T = 2015 Feb. 22.4895 TT         Peri. = 249.2766
     e = 0.852822                     Node  = 277.0964  2000.0
     q = 1.155759 AU                  Incl. = 172.5199
       a =  7.852781 AU    n = 0.0447887    P =  22.0 years


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2015 CBAT
2015 January 26                  (CBET 4060)              Daniel W. E. Green