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			25 Birch Street, Cambridge, MA 02138 USA 
			Tel. 617-354-0484	FAX 617-354-0665

			AAVSO ALERT NOTICE 219 (February 28,1996)


The old nova GK Per (Nova Per 1901) has gone into a minor outburst for the first time 
since 1992 (see AAVSO Alert Notice 159), as indicated by the following observations 
reported to the AAVSO:

Feb. 19.03 UT, 12.8, J. Bortle, Stormville, NY; 20.09, 12.9, W. Dillon, Missouri City, TX; 
23.13, 13.0, R. Royer, Lakewood, CA; 23.83, 12.9, P. Schmeer, Saarbrucken, Germany; 
25.0507, 12.7, M. A. Komorous, London, Ontario, Canada; 25.51, 12.8, G. Dyck, Assonet, 
MA; 25.819, 12.7, Schmeer; 25.873, 12.6, J. R. Osorio, Madrid, Spain; 26.0132, 12.8, G. 
Chaple, Townsend, MA; 26.0542, 12.4, J. McKenna, Upper Montclair, NJ; 26.0549, 12.5, 
Bortle; 26.51, 12.5, Dyck; 26.781, 12.4, Schmeer; 26.809, 12.4, Schmeer; 26.952, 12.2, G. 
Poyner, Birmingham, England; 26.9819, 12.5, Chaple; 27.0250, 12.4, Bortle; 27.0410, 12.2, 
McKenna; 27.0431, 12.0, C. Scovil, Stamford, CT; 27.0507, 12.2, T. Hager, New Milford, 
CT; 28.0972,12.1, A. Dill, Wichita, KS; 28.4535,11.8, S. Sakuma, Kawasaki, Japan.

The last outburst started on July 3, 1992, and by July 12 GK Per reached magnitude 10.8. It 
then slowly brightened to a mean magnitude of 10.3 by July 31, and it faded back to 
minimum by September 10, 1992. The accompanying light curve of observations in the 
AAVSO International Database shows the behavior of GK Per from JD 240000 to 2450000 
(May 1968 - October 1995).

The scatter between observers in the current observations may be due both to the 
comparison stars being used and, possibly, small fluctuations in the brightness of GK Per.

After timely notice by our observers to AAVSO Headquarters, we alerted astronomers at 
the University of Leicester, England, to the brightening of GK Per. They were able to 
schedule the satellite X-ray Timing Explorer (XTE) to observe GK Per on February 27, 
and this observation was carried out successfully. The Japanese X-ray astronomy satellite 
ASCA has also been scheduled to make an observation of GK Per on March 4 6:00-20:50 
(UT). A second XTE observation is expected to be made simultaneously with the ASCA 
one. Astronomers at the University of Leicester are also trying to obtain Hubble Space 
Telescope target-of-opportunity time to make time-resolved ultraviolet spectroscopy 

Your careful and dedicated monitoring and timely alerts enabled us to inform the 
astronomers so that they could trigger the observations of GK Per being made with these 
satellites. On behalf of the astronomical community and all of us at AAVSO, thank you!

Please monitor GK Per using the AAVSO 'e' and 'f charts distributed with AAVSO Alert 
Notice 211, and report your observations to AAVSO Headquarters. These charts may also 
be retrieved from our ftp site and home page (see below).


The 83 comparison star to the east in the field of N Cas 95 on the AAVSO 'b' chart has
been reported by some observers as a possible small-amplitude variable. Observers are 
strongly urged not to use this comparison star when making estimates of N Cas 95.


Electronic copies of the AAVSO charts of GK Per mentioned in this Alert Notice are 
available from our FT? site: (, in /pub/alert211

The AAVSO light curve of GK Per is also available from our FTP site: (, in /pub/alert219

The charts and light curve have also been placed on our home page:

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