Electronic Telegram No. 2253
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Room 209; Dept. of Earth and Planetary
 Sciences; Harvard University; 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbat@iau.org; cbatiau@eps.harvard.edu
URL http://www.cfa.harvard.edu/iau/cbat.html


COMET P/2010 H2 (VALES)
     P. Birtwhistle, Great Shefford, Berks., England, writes that observations
using a 0.40-m f/6.0 Schmidt-Cassegrain and identical exposures and
measurement settings indicate an increase in coma size from 26" by 24" on Apr.
17.1 UT to 38" by 34" on Apr. 18.1.  K. Hornoch, from co-added R-band frames
with the 0.65-m telescope at Ondrejov on Apr. 18.0, noted a very strongly
condensed elliptical coma of 65" by 50", with the long axis in p.a. 55-235 deg.
A. Novichonok and D. Chestnov, observing remotely at Cloudcroft, NM (0.18-m
f/2.8 Newtonian reflector), on Apr. 19.3, described an extended 1'.0 by 0'.8
coma of integrated magnitude V = 11.4.
     The improved orbit below, based on 356 observations extending to Apr. 19.6
(mean residual 0".2), taken from MPEC 2010-H26, confirms the general features
of that on CBET 2249, with the minimum distance from Jupiter in May 1976 now
refined to 1.0 AU.

     T = 2010 Apr. 24.769 TT          Peri. = 139.162
     e = 0.19957                      Node  =  64.420   2000.0
     q = 3.09157 AU                   Incl. =  14.183
       a = 3.86239 AU,  n = 0.129844 deg/day,  P = 7.59 years


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2010 CBAT
2010 April 19                    (CBET 2253)              Brian G. Marsden