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Special Notice #227: Unusual Behavior of FS Aur - Outburst Imminent?

January 3, 2011: The campaign to monitor activity of the peculiar cataclysmic variable FS Aurigae, as announced in AAVSO Alert Notice 428 (see also AAVSO Special Notice #226), continues. Principal Investigator Dr. Vitaly Neustroev reports that the campaign is going well, and that he is very appreciative of your observing efforts and contributions.

Special Notice #226: Request for observations of FS Aurigae

December 4, 2010: Further to AAVSO Alert Notice 428, the star FS Aurigae appears to be entering outburst.  The star was in quiescence on 2010 December 3.22 (JD 2455533.72; V = 16.3, G. Lubcke) but had risen to V=14.9 on 2010 December 4.23 (JD 2455534.73; R. Campbell).  Subsequent observations by H. McGee and A. Novichonok have confirmed that FS Aur is rising.  Time series observations of FS Aurigae are encouraged at this time; any and all filters may be used including clear, but V filter is preferred.

Special Notice #224: Possible outburst of SDSS_J160501.35+203056.9

November 21, 2010: Hitoshki Yamaoka reports in VSNET-ALERT 12411 of the observation by Itagaki of SDSS J160501.35+203056.9, a suspected cataclysmic variable.  In quiescence, it is about mag20.  Itagaki-san's observation on 2010-11-21 was 12.0 unfiltered.  If confirmed, this would yield an outburst magnitude of 8 magnitudes, and would place it in the realm of the WZ Sge class, rare stars in the cataclysmic category that have superoutburst cycles of decades.  The spectra in Szkody, et al.

Special Notice #221: Infrequent Outburst of the SU UMa Variable HT Cas

November 2, 2010: As reported by Tim Parson (Circle Pines, Minnesota, USA) and confirmed by Pavol Dubovsky (Kolonica, Slovakia), the infrequently-outbursting dwarf nova HT Cas is in outburst.  Parson observed HT Cas in outburst at m(vis)=12.9 on JD 2455502.93 (2010 November 2.43), and the outburst was confirmed by Dubovsky at m(vis)=12.4 on JD 2455503.3 (2010 November 2.8).  The last confirmed well-observed outburst of this star occurred on 2008 January 10.  Observations of this variable are strongly encouraged at this time.  Both visual and CCD observations are en

Special Notice #219: Eclipse of the symbiotic star CI Cygni

October 12, 2010: As noted by U. Munari et al (ATel #2913, 2010 October 9), the symbiotic star CI Cygni is currently undergoing an eclipse of the outbursting star.  CI Cyg has declined from about magnitude 9.7 in late August 2010 to V=11.1 currently.


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