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IAUC 5734: 1993I; GRO J0422+32; 1992t

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                                                  Circular No. 5734
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Telephone 617-495-7244/7440/7444 (for emergency use only)
TWX 710-320-6842 ASTROGRAM CAM     EASYLINK 62794505
MARSDEN@CFA or GREEN@CFA (.SPAN, .BITNET or .HARVARD.EDU)


SUPERNOVA 1993I IN MCG +2-32-144
     M. Turatto, C. Zanin and V. Buondi, Asiago Observatory, confirm
the existence of this object on CCD frames taken with the 1.8-m
telescope on Feb. 28, when the object, located 13".5 west and 8".4
south of the galaxy's nucleus, had B = 17.95, B-V = +0.20.

     A. Clocchiatti and J. C. Wheeler, University of Texas, report that a
spectrum (range 450-720 nm, dispersion 0.34 nm/pixel) obtained on Mar.
29.3 UT with the 2.7-m telescope of the McDonald Observatory shows
that SN 1993I is of type Ia close to maximum light.  The typical
spectral features show a redshift consistent with the radial velocity
of MCG +02-32-144 (12 924 km/s) reported by Zwicky in Stars and
Stellar Systems 8, 375.


GRO J0422+32
     C. Chevalier and S. A. Ilovaisky, Observatoire de Haute-Provence,
report: "New CCD photometry of the optical counterpart of this x-ray
transient has been obtained with the Haute-Provence 1.2-m telescope on
Jan. 19-23, Feb. 10-20 and Mar. 12-13.  When combined with the earlier
January data (IAUC 5692) our 1993 observations made on 23 nights over
a 2.5-month interval show that, after a slow-down in its decline during
early January just after the secondary x-ray maximum (IAUC 5685), the
average decline rate returned to a value near 0.01 mag/day, close to
what was seen earlier in the outburst (IAUC 5644, 5650).  This decay
rate is half that seen in V616 Mon = A0620-00 during its 1975 outburst.
On 1993 Mar. 13 the optical counterpart of GRO J0422+32 was 1.4 mag
fainter in V than in early Sept. 1992 when we started our monitoring
program.  Calibration of our differential photometry using Guide Star
Photometric Catalogue stars gives V = 14.6 for this March observation.
The 5.1-hr periodic modulation detected in the January data was also
present in February but with a reduced amplitude."


PERIODIC COMET SWIFT-TUTTLE (1992t)
     Total visual magnitude estimates: Feb. 24.76 UT, 9.2 (D. A. J.
Seargent, The Entrance, N.S.W., 25 x 100 binoculars); 26.76, 9.4
(P. Camilleri, Cobram, Vic., Australia, 20 x 80 binoculars);
Mar. 3.76, 9.7 (Camilleri); 21.77, 10.0 (Camilleri, 0.20-m reflector);
23.74, 10.2 (Camilleri).


1993 March 30                  (5734)              Brian G. Marsden

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