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AAVSO Alert Notice 384: Outburst of GK Persei AAVSO HOME > publications > alert notice

AAVSO Alert Notice 384

Outburst of GK Persei
September 24, 2008

As reported in AAVSO Special Notice #125, the cataclysmic variable GK Persei
appears to be entering another outburst.  The object began a slow rise on
or about 2008 September 10 UT (JD 2454719.5), rising nearly one magnitude
above its typical quiescent level of m(vis) = 13, to near m(vis) = 12.2
at present (2008 September 24 UT, JD 2454733.5).  This rate of brightening
is typical of past outbursts, and suggests a rise to full outburst may occur
soon.  However, this activity comes much sooner than expected based on past
intervals between outbursts, and the last outburst (2006 December 5, JD 
2454075) reached a much fainter maximum than normal -- about m(vis)=11.5, 
more than one magnitude fainter than the typical m(vis)=10.5-10.0.  Observers
are asked to closely follow GK Persei at all wavelengths during the current
outburst, however it may evolve.  Both visual and filtered CCD photometry
are strongly encouraged.

The most recent visual (M. Komorous) and V-band CCD (D. Lane) made around
2008 September 24.2 UT (JD 2454733.7) have GK Persei around m(vis) = 
12.2 to 12.3.

GK Persei (AUID 000-BBG-044) is located at the following J2000 coordinates:

RA: 03 31 12.00 , Dec +43 54 15.0

Charts for GK Per may be plotted using VSP:

Please promptly submit all observations to the AAVSO via WebObs.

Thanks to all observers who have reported GK Per in outburst and who have
submitted observations thus far!

Clear skies, and good observing,

Matthew Templeton


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