Electronic Telegram No. 2922
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/2011 W2 (RINNER)
     Claudine Rinner, Ottmarsheim, France, reports her discovery of a comet
with a 1' tail in p.a. 293 degrees on CCD images taken with a 0.5-m f/3
reflector located at the Oukaimeden Observatory near Marrakech, Morocco
(discovery observations tabulated below).  After posting on the Minor Planet
Center's NEOCP webpage, numerous other CCD astrometrists have also commented
on the object's cometary appearance from images obtained during Nov. 29.3-29.5
UT.  H. Sato (Tokyo, Japan; remotely using telescopes at the RAS Observatory
near Mayhill, NM, U.S.A.) writes that exposures taken with a 0.25-m f/3.4
reflector in bad seeing show magnitude 17.6 without an obvious coma, but with
an obvious tail 20" long in p.a. 275 deg; exposures taken with a 0.51-m f/4.5
reflector show a 13" coma and the same tail dimensions.  R. Ligustri (Udine,
Italy) also used a 0.25-m f/3.3 reflector remotely at the RAS Observatory near
Mayhill to find a coma elongated toward p.a. 270 deg (size 33").  E. Guido, G.
Sostero, and N. Howes write that stacked images taken remotely with a 0.25-m
f/3.4 reflector at the GRAS Observatory near Mayhill show a diffuse coma
nearly 15" in diameter.  J. V. Scotti reports that images taken with the
Spacewatch 1.8-m f/2.7 reflector (+ Schott OG-515 filter, spanning V + R + I;
pixel size 0".62) shows a diffuse coma of diameter 7" with a tail extending
0'.30 in p.a. 289 deg.  G. Hug (Scranton, KS, U.S.A., 0.56-m reflector) notes
a broad tail extending 1' in p.a. 285 degrees.

     2011 UT             R.A. (2000) Decl.       Mag.   Observer
     Nov. 28.12723    7 57 45.14   + 5 36 54.5   17.9   Rinner
          28.14138    7 57 45.27   + 5 36 45.8   18.0     "
          28.15552    7 57 45.36   + 5 36 37.2   17.9     "
          28.16967    7 57 45.50   + 5 36 28.3   17.9     "

The available astrometry, the following very preliminary elliptical orbital
elements by G. V. Williams, and an ephemeris appear on MPEC 2011-W80.

     T = 2011 Oct. 10.616 TT          Peri. = 210.504
     e = 0.51202                      Node  = 233.758   2000.0
     q = 2.31556 AU                   Incl. =  14.202
       a =  4.74524 AU     n = 0.095349     P =  10.3 years


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2011 CBAT
2011 November 29                 (CBET 2922)              Daniel W. E. Green