Electronic Telegram No. 3878
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/2014 K2 = 2007 RJ_236 (LEMMON-PANSTARRS)
     Bryce Bolin, Richard Wainscoat, Marco Micheli, Henry Hsieh, and Larry
Denneau report the discovery of a diffuse comet on four 45-s w-band exposures
from the Pan-STARRS1 telescope on Haleakala on May 21 (discovery observations
tabulated below).  Three 60-s R-band follow-up exposures obtained with the
Canada-France-Hawaii Telescope (+ Megaprime camera; queue observer Lisa Wells)
on May 22 confirm the cometary appearance and indicate a hint of asymmetric
extension toward p.a. 120 degrees.  Additional Pan-STARRS1 images were then
found on Apr. 29.

     2014 UT             R.A. (2000) Decl.       Mag.
     May  21.39261   14 41 08.89   - 7 43 13.2   21.4
          21.40462   14 41 08.48   - 7 43 12.0   21.5
          21.41662   14 41 08.07   - 7 43 10.6   21.2
          21.42859   14 41 07.67   - 7 43 09.4   21.2

G. V. Williams then linked these May 21 observations with an object discovered
via the Mount Lemmon Survey 1.5-m reflector on 2007 Sept. 13 (discovery
observations tabulated below; observer E. C. Beshore), when it was reported as
apparently asteroidal at four different observatories (2007 Aug. 16-Oct. 2)
and given the minor-planet designation 2007 RJ_236 on MPS 217811 (and MPS
280214).

     2007 UT             R.A. (2000) Decl.       Mag.   Observer
     Sept.13.30374   22 53 49.16   -13 11 33.7   19.3   Beshore
          13.31041   22 53 48.91   -13 11 35.2   19.3     "
          13.31708   22 53 48.69   -13 11 36.8   19.3     "
          13.32375   22 53 48.44   -13 11 38.7   19.4     "

The available astrometry, the following linked orbital elements by G. V.
Williams (from 28 observations spanning 2007 Aug. 16-2014 May 22; mean
residual 0".4), and an ephemeris appear on MPEC 2014-K28.

                    Epoch = 2007 June 29.0 TT
     T = 2007 July  4.62049 TT        Peri. = 208.20226
     e = 0.2304461                    Node  = 121.82905 2000.0
     q = 3.2776578 AU                 Incl. =   6.03791
       a =  4.2591659 AU   n = 0.11212882   P =   8.790 years

                    Epoch = 2016 May  12.0 TT
     T = 2016 Apr. 30.50919 TT        Peri. = 208.26880
     e = 0.2283900                    Node  = 121.78149 2000.0
     q = 3.3026600 AU                 Incl. =   6.03092
       a =  4.2802195 AU   n = 0.11130252   P =   8.855 years


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2014 CBAT
2014 May 23                      (CBET 3878)              Daniel W. E. Green