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Special Notice #121: Outburst of the symbiotic star CI Cygni

August 31, 2008

As noted by J. Toone and G. Poyner on the BAAVSS-alert mailing list, the symbiotic star CI Cyg appears to be undergoing its first major outburst since March 1975.  The star apparently began to rise from approximately m(vis) = 11.0 on or about JD 2454690 (2008 August 11), and rapidly brightened by more than one magnitude over the past three weeks.  Recent observations suggest CI Cyg may be at or near maximum light.  Visual observations and instrumental photometry are strongly encouraged.

The most recent observations of CI Cyg submitted to the AAVSO are: m(vis) = 9.7, JD 2454709.4840 (S. Swierczynski, Dobczyce, Poland); 10.1, 2454709.3743 (H. Hautecler, Boutersem, Belgium); 9.7, 2454709.2910 (W. Kriebel, Schierling, Germany); 9.5, 2454708.4472 (H. Hautecler); 9.9, 2454707.7625 (P. Abbott, Leduc, Alberta, Canada); 9.9, 2454707.4049 (E. Muyllaert, Oostende, Belgium); 9.7, 2454707.3306 (F. Gobet, Cestas, France); 9.8, 2454707.3090 (G. Mavrofridis, Nikea, Greece).

CI Cygni is located at RA: 19h 50m 11.8s , Dec: +35d 41m 03s (J2000)

Charts for CI Cygni may be generated with VSP:

Please report all observations to the AAVSO as CI Cyg (AUID 000-BCJ-172).

This AAVSO Special Notice was prepared by Matthew Templeton.


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