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			THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS 
				25 Birch Street, Cambridge, MA 02138 USA
					INTERNET: aavso@aavso.org

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

				AAVSO ALERT NOTICE 224 (July 24,1996)

2327-54 SUPERNOVA 1996a1 IN NGC 7689

We have been informed by the Central Bureau of Astronomical Telegrams (IAU Cincular 6437) of the 
visual discovery of a supernova in NGC 7689 by Robert Evans and R. Benton, Coonabarabran, New 
South Wales, and Samantha Beaman, Pimpama, Queensland, Australia, on July 22.71 UT at magnitude 
approximately 14.0, using the Australian National University 1-m telescope at Siding Spring. The 
supernova is about 30" north of the center of the galaxy, and does not appear on earlier European 
Southern Observatory (ESO) survey films or CCD survey images.

The position of SN 7689 was measured by J. Pogson and S. Ryan, Anglo-Australian Observatory (IAU 
Circular 6437) as:

RA = 23h 33m 16.1s Decl. = -54 05' 02" (2000).

The supernova was confirmed by S. Benetti, ESO, and R. Neuhauser, Max-Planck- Institut, Garching, 
Germany, on inspection of a preliminarily-reduced CCD spectrum taken with the ESO 1.52-m telescope 
at La Silla, Chile, on July 23.35 UT, as a type II supernova discovered soon after explosion (IAU Circular 
6438). The spectrum also showed evidence of circumstellar material, probably lost by the supernova 
progenitor before exploding, and is expected to evolve rapidly (IAU Circular 6438).

Accompanying is a chart from the AAVSO Variable Star Atlas showing the location of NGC 7689, and a 
chart, with insets, of the galaxy and the supernova from the Deep Space CCD Atlas: South by Vickers 
and Wassilieff. Magnitudes on this chart are taken from the Guide Star Catalog, using The Sky software. 
Please monitor SN 7689 and report your observations to AAVSO Headquarters.

Congratulations to Bob Evans, R. Benton, and Samantha Beaman on their discovery!

CHARTS AVAILABLE ON AAVSO FTP SITE AND AAVSO WEB SITE HOME PAGE

Electronic copies of the charts mentioned in this Alert Notice are available from our FTP site:

ftp.aavso.org (198.116.78.2), in /pub/alert224

The charts have also been placed on our Web site at the following address:

http://www.aavso.org

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. If you are cut off when 
you telephone in your observations, please wait a few minutes and call back to complete your call. We 
have learned that if someone calls to leave observations on the answering machine and while they are 
speaking someone else calls, the first person may be cut off. We also encourage observers to send 
observations by fax to 617-354-0665 or by e-mail through the Internet to observations@aavso.org. We 
would appreciate it very much if you would report your observations in Universal Time.

Many thanks for your valuable astronomical contributions and your efforts.

Good observing!

Keywords:
AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484