[IAUC] CBET 3979: 20140919 : COMET C/2011 J2 (LINEAR)

Jue Sep 18 19:41:21 ART 2014

                                                  Electronic Telegram No. 3979
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 C/2011 J2 (LINEAR)
     F. Manzini, V. Oldani, and A. Dan, Stazione Astronomica di Sozzago,
Italy; R. Crippa, Osservatorio di Tradate, Italy; and R. Behrend, Geneva
Observatory, report that comet C/2011 J2 (cf. IAUC 9208) was observed with the
0.4-m telescope at Sozzago during about 40 min per night around Aug. 27.95,
28.85, and 30.91 UT.  Carefully stacked images show, for both nights, a
second, fainter, nuclear condensation located 0".8 east and 7".5 north of the
main, brighter nuclear condensation on an image scale of 0".7/pixel.  The
newly detected condensation was then about 1.5 mag fainter than the brighter
one.  No relative motion was detected between the two nights.  The coma was
roughly circular and 50" in diameter, with a 1'-long, faint, diffuse tail
visible in p.a. 50 deg.  Manzini and Behrend obtained additional exposures
with the Sozzago 0.4-m f/6.6 reflector on Sept. 14.0 that show secondary
component B to be 2.5 mag fainter than primary component A, with component B
located 1".6 east and 9".6 north of component A.  Behrend estimates that the
date of separation was July 14 +/- 10 days.
     Numerous other reports of descriptive information from other CCD
observers have been received from other observers, with a summary given below.
Astrometry of both components have been poublished on MPECs 2014-R69 and
2014-R70, and on MPCs 89407 and 89408.
     E. Bryssinck, Kruibeke, Belgium, reports that C/2011 J2 was observed with
a 0.2-m f/7 refractor (+ Luminance filter) by A. Diepvens (Balen, Belgium) on
Aug. 28.88 UT; the stacked images show component B to be 7".5 from component
A in p.a. 4 deg.  Bryssinck observed the comet on Sept. 2.39 with an
iTelescope 0.62-m f/6.5 reflector (+ Luminance filter) at Auberry, CA, USA,
showing component B to be 8".9 from component A in p.a. 10 deg (and 1.6-3.0
mag fainter).  Bryssinck's images from Sept. 17.02 show component B to be
2.3 mag fainter than component A and 11".3 distant in p.a. 9.6 degrees (0.4-m
f/3.8 reflector).
     L. Buzzi, Varese, Italy, writes that stacked exposures taken with a
0.38-m f/6.8 reflector on Sept. 3.0 UT show component B to be 2.9 mag
fainter than component A and offset 0".8 east and 8".5 north; he infers
that component B then showed a diffuse coma around 5" wide without a clear
central condensation, making astrometry quite difficult.
     G. Tancredi, D. Lazzaro, T. Rodrigues, and R. Souza report that they
observed the comet with the 1-m telescope of the Observatorio Astronomico do
Sertao de Itaparica in Brazil during Sept. 3.12-3.14 UT; their stacked images
show component B to be 3 mag fainter than component A and located 8".7 away
in p.a. 11 deg.
     Images obtained at the Mirasteilas Observatory at Falera, Switzerland,
by J. De Queiroz and R. Behrend with a 0.90-m f/6.7 reflector on Sept. 3.9
and 4.0 show component B to be 2.5 mag fainter than component A and located
0s.16 east and 8".4 north.
     Observations obtained by E. Frappa (Planetarium de St-Etienne, France),
M. Lavayssiere (Observatoire de Dax, France), and R. Behrend (Geneva
Observatory) with the 1.05-m f/12.7 reflector at Pic-du-Midi Observatory on
Sept. 4.01-4.05 UT show component B to be 2.5 mag fainter than component A.
The total coma diameter is more than 90' in thirty stacked 60-s images, and
there is no additional fragment visible down to mag 23.  Additional images
were taken with the same telescope by Frappa et al. on Sept. 5.1, showing
component B to be 3.0 mag fainter than component A and located about 1".5
east and 8".6 north of the brighter component.
     L. Buzzi and S. Foglia stacked eleven 45-s images taken in good seeing
(FWHM = 1".0) with the 2.0-m "Faulkes Telescope North" at Haleakala on Sept.
4.4, showing component B to have an R-band magnitude around 20.5 in an
aperture of size 1".5; it was about 3.5 mag fainter than component A, was
offset 1".5 east and 8".7 north, and showed a diffuse central condensation 2"
wide that was surrounded by a coma at least 5" wide.
   Images obtained by G. Masi and P. L. Catalano (measured by G. Masi and U.
Masi) with a 0.43-m f/6.8 reflector at Ceccano, Italy on Sept. 7.8 UT in
bright moonlight show component B to be about 2.4 mag fainter than component A
with a size of a few arcseconds in stacked images.  Additional images taken
by G. Masi on Sept. 13.0 and 13.8-13.9 show component B as before, easily
visible despite moonlight.
     Images obtained by P. Bacci (measured by Bacci, L. Tesi, and G. Fagioli)
with a 0.60-m f/4 reflector at San Marcello Pistoiese, Italy, on Sept. 14.0 UT
show component B at magnitude about 16.5, about 2 mag fainter than component A
and offset 9".7 in p.a. 14 deg.
     J. Carrillo obtained images on Sept. 15.9 UT with a 0.36-m f/5 reflector
at Fuensanta de Martos, Spain, that show component B to be 4 mag fainter than
component A.

     Total-magnitude and coma-diameter estimates for component A:  Feb. 22.45
UT, 14.0, -- (K. Kadota, Ageo, Japan, 0.25-m reflector + CCD); 28.78, 13.2,
0'.3 (U. Pilz, Leipzig, Germany, 32-cm reflector; visual); May 2.77, 14.1, --
(Kadota); 30.72, 14.4, -- (Kadota); July 28.65, 14.1, -- (Kadota); Aug. 1.03,
13.2, 1'.2 (Pilz); 3.01, 13.5, 0'.93 (M. L. Paradowski, Dabrowa, Poland,
0.30-m reflector; visual); 18.63, 14.0, -- (Kadota).  The total brightness
has remained fairly close to the prediction in the ICQ's 2014 Comet Handbook,
with no obvious large outburst associated with an outburst seen in these
data reported to the ICQ and the Central Bureau.


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                         (C) Copyright 2014 CBAT
2014 September 19                (CBET 3979)              Daniel W. E. Green