Circular No. 6308

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                                                  Circular No. 6308




Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
>Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
BMARSDEN@CFA.HARVARD.EDU or DGREEN@CFA.HARVARD.EDU (science)
Phone 617-495-7244/7440/7444 (for emergency use only)


COMET C/1995 O1 (HALE-BOPP)
     H. U. Kaufl, European Southern Observatory; and H. Bohnhardt,
Institute for Astronomy and Astrophysics, University of Munich,
report that G. van der Steene observed this comet with the 3.5-m
New Technology Telescope on Feb. 9.35 UT, just before the onset of
astronomical twilight.  A preliminary analysis shows that isophotes
of the coma are detectable out to a radius of 2'.5 from the nucleus
and that the fan-shaped coma is strongly elongated to the north.
Using R filters, they find the following photometric magnitudes for
the inner coma (centered on the nucleus):  11"x14", 8.9; 28"x28",
7.9; 39"x39", 7.6.  A logarithmic image is available on the WWW at
http://www.eso.org/comet-hale-bopp/phot-10-96.html.


COMET C/1995 Y1 (HYAKUTAKE)
     J.-L. Bertaux, Service d'Aeronomie du CNRS, writes:  "On Feb.
6, the SWAN instrument, a full-sky Lyman-alpha imager onboard the
SOHO spacecraft, measured the hydrogen cloud around comet C/1995 Y1.
From the Lyman-alpha brightness and extension of the cloud (4
degrees), a rough estimate of the water-vapor production was
determined to be 1.5 x 10E28 hydrogen molecules/s.  The monitoring
of this hydrogen cloud will be continued on a regular basis in the
coming months."
     Total visual magnitude estimates (cf. IAUC 6293):  Jan. 24.52
UT, 9.4 (A. Hale, Cloudcroft, NM, 10x50 binoculars); 30.18, 8.3 (K.
Hornoch, Lelekovice, Czech Republic, 0.35-m reflector); Feb. 1.20,
8.4 (A. Diepvens, Balen, Belgium, 0.15-m refractor); 1.44, 8.2 (J.
E. Bortle, Stormville, NY, 20x80 binoculars; coma diameter 5'.5).


NOVA CASSIOPEIAE 1995
     Visual magnitude estimates:  Jan. 7.10 UT, 9.2 (A. Pereira,
Cabo da Roca, Portugal); 16.77, 9.0 (A. R. Baransky, Kiev, Ukraine);
21.22, 9.4 (A. Hale, Cloudcroft, NM); 24.79, 9.1 (R. Goncalves,
Oeiras, Portugal); 29.82, 9.2 (Goncalves); Feb. 3.81, 9.5 (M. V.
Zanotta, Laino, Italy).


GRO J1744-28
     Corrigendum.  On IAUC 6307, line 10, for  +/- 30 mJy   read
+/- 30 microJy

                      (C) Copyright 1996 CBAT
1996 February 9                (6308)            Daniel W. E. Green