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                AAVSO ALERT NOTICE 267 (December 10, 1999)

1012+41 SUPERNOVA 1999gi IN NGC 3184

We have been informed by the Central Bureau for Astronomical Telegrams (IAU
Circular 7329 - http://cfa-www.harvard.edu/iau/cbat.html) that S. Nakano,
Sumoto, Japan, reports that Reiki Kushida, Yatsugatake South Base Observatory
(YSBO), Japan, discovered a supernova in NGC 3184 on Dec. 9.82 UT at
unfiltered CCD magnitude 14.5, using a 0.40-m reflector.  Kushida reported that
nothing was visible at the location of the supernova down to magnitude 18 on
CCD images obtained by her between 1994 and May 6, 1999.  W. Li, University of
California at Berkeley, reported that nothing was visible at the position of
the supernova down to magnitude 19.0 on a KAIT image of NGC 3184 taken on
Dec. 2.5 UT.

A precise position of SN 1999gi, which is 3.5" west and 60.5" north of the
center of the galaxy, was obtained by Y. Kushida, YSBO, from R. Kushida's CCD
image and reported by Nakano (IAU Circular 7329) as:

     R.A. = 10h 18m 16.66s   Decl.= +41 degrees 26' 28.2" (Equinox 2000.0)

S. Jha, P. Garnavich, P. Challis, and R. Kirshner, Harvard-Smithsonian Center
for Astrophysics, report that A. Mahdavi and Jha obtained CCD spectroscopic
observations on Dec. 10.42 UT using the F. H. Whipple Observatory 1.5-m
telescope (+ FAST spectrograph) that showed that the supernova is Type II, at
an early epoch (IAU Circular 7329).

Accompanying is a chart prepared by K. Malatesta, AAVSO Headquarters, using
an image from the Digitized Sky Survey and comparison star magnitudes from the
Hipparcos and Tycho Catalogues, the USNO A2.0 Catalogue, and H. G. Corwin
(Thompson and Bryan, The Supernova Search Charts and Manual).  Please use this
chart to observe 1012+41 SN 1999GI and report your observations to AAVSO
Headquarters so we may inform the astronomical community.  Please be sure to
indicate which comparison stars you used.

Congratulations to Reiki Kushida on her latest discovery!


Electronic copies of the SN 1999gi chart mentioned in this Alert Notice are
available through our web site at the following address:


The charts may also be obtained directly from our FTP site:

       ftp.aavso.org (, in /alerts/alert267

The answering machine at AAVSO Headquarters is on nights and weekends for
your convenience. Please call our charge-free number (888-802-STAR =
888-802-7827) to report your observations. We also encourage observers to
send observations by fax to 617-354-0665 or by e-mail through the Internet
to observations@aavso.org.

Many thanks for your valuable astronomical contributions and your efforts.

Good observing!

Janet A. Mattei

Elizabeth O. Waagen
Senior Technical Assistant