Electronic Telegram No. 3649
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 C/2013 R1 (LOVEJOY)
     Terry Lovejoy, Thornlands, Qld., Australia, reports his discovery of a
comet on CCD images obtained with a 20-cm f/2.1 Schmidt-Cassegrain reflector
on two nights, the object showing a small, condensed coma about 0'.5 in
diameter with a diffuse tail pointing westward; the discovery astrometry is
tabulated below.  Following posting on the Minor Planet Center's NEOCP
webpage, other CCD astrometrists have also commented on the object's cometary
appearance.  E. Guido, Castellammare di Stabia, Italy, writes that images
obtained by N. Howes and himself with a 0.32-m f/9 Ritchey-Chretien reflector
at the iTelescope Observatory, Siding Spring, on Sept. 8.7 UT shows a sharp
central condensation surrounded by a coma about 25" in diameter and a tail
about 40" long in p.a. 245 deg.  H. Sato, Tokyo, Japan, notes that images
taken with a 0.32-m f/8 astrograph (+ broadband luminance filter) at the RAS
Observatory near Nerpio, Spain on Sept. 9.2 reveals a strongly condensed coma
of diameter 45", with magnitude 14.5 as measured within a circular aperture of
radius 23".4, and a fan-like tail 40" long toward p.a. 260 degrees; his
follow-up images on Sept. 9.7 with a 0.51-m f/6.8 astrograph at the iTelescope
Observatory, Siding Spring, show a strongly condensed coma whose outer diameter
was larger than 3', of magnitude 13.0 as measured within a circular aperture
of radius 73".8, with a fan-like tail 60" long toward p.a. 250 degrees.
T. Lister finds a large, bright coma of diameter about 11" on V-band images
taken with a 1.0-m f/8 Ritchey-Chretien reflector at Cerro Tololo on Sept. 9.4.
G. Hug (Scranton, KS, U.S.A., 0.56-m reflector; Sept. 9.4) found a "broad
coma toward p.a. about 270 deg".  A. Novichonok reports a slightly elongated
coma of diameter 1'.4 with total red mag 13.1 on four 45-s exposures taken
remotely with a 0.32-m f/9.3 Ritchey-Chretien reflector at the iTelescope
observatory at Siding Spring on Sept. 9.7.  K. Kadota (Ageo, Saitama-ken,
Japan; 0.25-m f/5 reflector; Sept. 9.77) finds the object to be diffuse with a
strong central condensation and a coma of diameter 2'.4 and total mag 13.1,
with a tail 0'.8 long in p.a. 253 deg.  R. Ligustri (Talmassons, Udine, Italy;
remotely using a 0.50-m f/4.5 reflector at the iTelescope Observatory, Siding
Spring, on Sept. 9.8) reports a 60" coma.  A. Hale, Cloudcroft, NM, U.S.A.,
notes that he detected the comet visually on Sept. 9.46 with a 0.41-m
reflector, the object appearing faint and fairly small, of total mag 14.0 with
an obvious 0'.6 coma that was moderately condensed.

     2013 UT             R.A. (2000) Decl.       Mag.   Observer
     Sept. 7.68794    5 58 09.04   - 6 39 14.2   14.4   Lovejoy
           7.69392    5 58 09.62   - 6 39 12.4   14.3     "
           7.70000    5 58 10.15   - 6 39 09.0   14.6     "
           8.63707    5 59 34.59   - 6 33 26.6   14.6     "
           8.64498    5 59 35.27   - 6 33 23.6   14.8     "
           8.65287    5 59 35.97   - 6 33 20.6   14.4     "

The available astrometry, the following preliminary parabolic orbital elements
by G. V. Williams, and an ephemeris appear on MPEC 2013-R72.

     T = 2013 Dec. 25.7887 TT         Peri. =  63.2668
                                      Node  =  72.9172  2000.0
     q = 0.877238 AU                  Incl. =  61.9418


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

                         (C) Copyright 2013 CBAT
2013 September 9                 (CBET 3649)              Daniel W. E. Green