[IAUC] IAUC 9213: C/2011 L2; 174P [25139-2011/04-R1]

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                                                  Circular No. 9213
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
New postal address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
CBATIAU en EPS.HARVARD.EDU           ISSN 0081-0304
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Prepared using the Tamkin Foundation Computer Network


COMET C/2011 L2 (McNAUGHT)
     Robert H. McNaught reports his discovery of a comet (discovery
observation tabulated below) on CCD images taken with the 0.5-m
Uppsala Schmidt telescope at Siding Spring, the discovery images
showing a 15" diffuse coma with little condensation; his follow-up
images on June 3.68 and 3.75 UT show the object to be moderately
condensed with a weak extension to west.  After posting on the
Minor Planet Center's 'NEOCP' webpage, other CCD astrometrists have
commented on the object's cometary appearance.  R. Holmes (Ashmore,
IL, USA), T. Linder, and V. Hoette obtained forty co-added 30-s
images remotely with a 0.41-m reflector at Cerro Tololo in 1".6
seeing on June 3.4 that show an elongated coma of diameter 8".6
with a very broad, faint tail extending 14" in p.a. 347 deg.
Images taken by A. C. Gilmore and P. M. Kilmartin with the Mt. John
1.0-m f/7.7 reflector on June 6.6 show a coma diameter of about 12"
and no tail in stacked exposures totalling 440 seconds.

     2011 UT             R.A. (2000) Decl.       Mag.   Observer
     June  2.78376   22 35 39.84   -26 46 14.1   18.1   McNaught

The available astrometry, the following preliminary parabolic
orbital elements by G. V. Williams, and an ephemeris appear on MPEC
2011-L27.

     T = 2011 Oct. 31.755 TT          Peri. = 256.183
                                      Node  = 131.331   2000.0
     q = 1.96489 AU                   Incl. = 104.023


COMET 174P/ECHECLUS = (60558) ECHECLUS
     M. Jaeger, Vienna, reports that he found comet 174P to be in
outburst at total mag 15.0 with a 1' coma on images taken on May
30.0 UT with a 0.25-m f/3.8 reflector at Stixendorf, Austria, by E.
Prosperi, S. Prosperi, W. Vollmann, and himself.  H. Sato (Tokyo,
Japan) reports that his images taken remotely with a 0.25-m
reflector (RAS Observatory near Mayhill, NM, U.S.A.) on May 30.2
show a coma of size 1' and total mag 15.1.  G. Sostero and E. Guido
obtained unfiltered CCD images remotely on June 1.6 with a 0.15-m
refractor at the Tzec Maun Observatory near Moorook, Australia,
that show a faint, spiral-like coma of total mag about 16 and
diameter 40" surrounding a sharp central condensation or red mag
about 18, with a jet-like feature nearly 6" long toward p.a. 60 deg.

                      (C) Copyright 2011 CBAT
2011 June 6                    (9213)            Daniel W. E. Green