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 219 (February 28,1996) MINOR OUTBURST OF 0324+43 GK PERSEI 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 observations. 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). 0059+53 NOVA CASSIOPEIAE 1995 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. CHARTS AVAILABLE ON AAVSO FTP SITE AND AAVSO HOME PAGE Electronic copies of the AAVSO charts of GK Per mentioned in this Alert Notice are available from our FT? site: ftp.aavso.org (198.116.78.2), in /pub/alert211 The AAVSO light curve of GK Per is also available from our FTP site: ftp.aavso.org (198.116.78.2), in /pub/alert219 The charts and light curve have also been placed on our home page: 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. 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 Director