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                   Tel. 617-354-0484       FAX 617-354-0665

                    AAVSO ALERT NOTICE 246 (April 15, 1998)

1151+55 SUPERNOVA 1998aq IN NGC 3982

We have been informed by Guy M. Hurst (The Astronomer Electronic Circ. 1288)
and by the Central Bureau for Astronomical Telegrams (IAU Circular 6875)
of the discovery by Mark Armstrong, Rolvenden, UK, of an apparent supernova
of magnitude 14.9 on unfiltered CCD images obtained on Apr. 13.049, 13.080,
and 13.109 UT.  The CCD images were taken with a 0.26-m reflector during
the course of searches of the UK Nova/Supernova patrol.

The object is located at:

    R.A. = 11h 56m 26s.00    Decl. = +55 degrees 07' 38".8  (equinox 2000.0)

Ron Arbour, South Wonston, UK, confirmed the presence of the object on
unfiltered CCD images taken on Apr. 13.086 and Apr. 13.814 UT with a 0.30-m
reflector.  He estimated the object to be 18" west and 07" north of the
nucleus of NGC 3982.  Hurst estimated the brightness at approximately
magnitude 14.5 on the latter exposure.

Earlier patrol photos by Armstrong on Mar. 9 and Apr. 7, 1998 did not
show the object.  There is no star at the above position to magnitude 19
in the USNO A1.0 Catalogue.

Accompanying is an AAVSO 'e' scale Supernova Search Preliminary chart of
NGC 3982, prepared by C. Scovil and showing the location of SN 1998aq.
Please use this chart to observe the supernova, and report your observations
of 1151+55 SN 1998aq to AAVSO Headquarters, making sure you indicate which
comparison stars you used.

Congratulations to Mark Armstrong on his third supernova discovery, and to the
UK Nova/Supernova Search team on their eighth supernova discovery!


Electronic copies of the AAVSO chart of SN 1998aq in NGC 3982 mentioned in
this Alert Notice are available from our FTP site:

   (, in /pub/alerts/alert246
 (, in /pub/charts/uma/SN1998aq/

The chart may also be accessed through our Web site at the following address:


The answering machine at AAVSO Headquarters is on nights and weekends for your
convenience.  Please call our charge-free number (800-642-3883) 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

Many thanks for your valuable astronomical contributions and your efforts.

Good observing!

Janet A. Mattei

AAVSO 49 Bay State Rd. Cambridge, MA 02138 617-354-0484