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IAUC 6004: 1993ak; 1993p; N Oph 1994

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                                                  Circular No. 6004
Central Bureau for Astronomical Telegrams
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

SUPERNOVA 1993ak IN UGC 8685
     C. Pollas, Observatoire de la Cote d'Azur, reports an
independent discovery a few months ago of this object (IAUC 6000)
on a pair of films obtained on 1993 Mar. 15.08 UT at mv about 18.5;
his private requests at that time to supernova search groups
yielded no confirmation.  He provides the following accurate
position for SN 1993ak:  R.A. = 13h40m54s.12, Decl. = +30o35'16".9
(equinox 1950.0), which is 27".4 east and 4".2 south of the
galaxy's nucleus.  A nearby stellar object of mag 18 has end
figures 50s.69, 34'54".5.  The object is not visible on two films
obtained 1994 Mar. 6.

     A. C. Gilmore, Mount John University Observatory, communicates
that a triple exposure of 5, 5, and 3 min on May 4.43 UT showed a
diffuse, roughly parabolic patch--brighter at the apex--at the
position of this object (cf. IAUC 5995).  There was no hint of the
small condensation that was present on Apr. 14.34 and well recorded
in 1- and 2-min exposures.  A double exposure of 10 and 15 min on
May 5.38 and 5.39 confirmed the previous night's images:  a roughly
parabolic envelope or fan about 4' long, with axis along p.a. 150
deg, and no hint of condensation where a reasonably stellar
condensation of mag 16-17 would have been recorded.
     J. V. Scotti, Lunar and Planetary Laboratory, reports that
observations on June 2.163 and 2.170 at large airmass by R. Jedicke
with the Spacewatch Telescope revealed a diffuse and uncondensed
image with no evidence of a nuclear condensation.  The diffuse coma
appeared as a roughly elliptical, nearly uniform image with its
long axis aligned from p.a. 151 to 331 deg (dimensions about 3'.5 x
1'.8).  The total coma magnitude was near 10.5.  The end of the
ellipse toward p.a. 331 deg appeared sharper than the opposing edge,
giving the appearance of a comet with a broad, diffuse tail
extending about 4' towards the south of the center of the
elliptical image of the coma.  Any remaining nucleus must have been
fainter than V about 18.5.

     Corrigendum.  A. Filippenko reports that further analysis of
the spectrum of N Oph 1994 obtained by Van Dyk et al. (IAUC 6002)
shows that the "forbidden lines" are actually permitted lines,
mostly Fe II.

1994 June 8                    (6004)            Daniel W. E. Green

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