[IAUC] CBET 3684: 20131030 : COMET P/2011 CR_42 (CATALINA)

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 3684
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 en eps.harvard.edu (alternate cbat en iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


COMET P/2011 CR_42 (CATALINA)
     An apparently asteroidal object discovered on images taken by A. Boattini
in September 2011 (discovery observations tabulated below), and then given the
minor-planet designation 2011 CR_42 by the Minor Planet Center, has finally
been confirmed to show cometary appearance following only a single known
marginal report of cometary activity near the time of discovery (cf. CBET
2823).  Further to that report two years ago, A. Waszczak reports that new
thirty stacked 60-s exposures obtained on 2013 Sept. 25.35-25.36 UT with the
1.5-m f/8.75 telescope at Palomar show the object to be extended, with its
approximate FWHM being 5", vs. nearby stars having a FWMH of 2".1; Waszczak
measured a red magnitude of 19.5.  H. Sato (Tokyo, Japan; remotely with an
iTelescope 0.51-m f/6.8 astrograph at Siding Spring) writes that ten stacked
60-s exposures taken on Oct. 1.6 show a moderately condensed coma 12"-15" in
diameter with no obvious tail, and his follow-up observations on Oct. 9.5
show a weakly condensed coma of diameter 12" in four stacked 120-s exposures;
he adds that the object was not found down to mag 21.0 on 2012 July 14.25 in
ten stacked 60-s exposures obtained with an iTelescope 0.50-m f/4.5
astrograph near Mayhill, NM, U.S.A.  Luca Buzzi writes that he obtained
follow-up observations on Oct. 30.54-30.55, via six stacked 180-s exposures
using the 2.0-m f/10 "Faulkes Telescope South" (+ Bessell R filter) at Siding
Spring, which show a very diffuse aspect in average seeing, with a 10" coma
and a possible extension to the northwest.

     2011 UT             R.A. (2000) Decl.       Mag.    Observer
     Feb. 10.46735   11 39 45.64   +15 09 18.8   17.6   Boattini
          10.47645   11 39 45.39   +15 09 21.6   17.7     "
          10.48549   11 39 45.14   +15 09 24.3   17.7     "
          10.49457   11 39 44.89   +15 09 26.9   17.7     "

The available astrometry, the following elliptical orbital elements by G. V.
Williams, and an ephemeris appear on MPEC 2013-U85.

                    Epoch = 2011 Nov. 15.0 TT
     T = 2011 Nov. 29.93164 TT        Peri. = 173.50538
     e = 0.2800248                    Node  =  58.74231 2000.0
     q = 2.5283172 AU                 Incl. =   8.45955
       a =  3.5116727 AU   n = 0.14977283   P =   6.58 years


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

                         (C) Copyright 2013 CBAT
2013 October 30                  (CBET 3684)              Daniel W. E. Green