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Special Notices

Special Notice #261: Outburst of the UGWZ Candidate BW Scl

October 21, 2011: The short period cataclysmic variable BW Scl appears to be in outburst. The object was detected in outburst at m(vis)=9.6 by M. Linnolt on 2011 October 21.3146 (JD 2455855.8146), and confirmed by A. Plummer at m(vis)=9.4 on October 21.3424.  Observations of this object are encouraged.  The object has conflicting classifications in astronomical literature, but is probably a WZ Sge-type dwarf nova rather than a novalike variable.

BW Scl is located at the following (J2000) coordinates:

Special Notice #250: Possible Type-Ia Supernova in M101

August 24, 2011: P. Nugent et al. report in ATel #3581 that a possible Type-Ia supernova has been discovered by the Palomar Transient Factory shortly after eruption in the galaxy M101 and has been designated "PTF11kly".  The object is currently at a magnitude of g=17.2, but may well rise by several magnitudes. The object is well placed within M101 for good photometry, and observations of this potential bright SNIa are strongly encouraged.

The (J2000) coordinates reported for the object are

    RA: 14:03:05.81 , Dec: +54:16:25.4

Special Notice #235: Request for archival data: V1647 Ori and McNeil's Nebula

February 15, 2011: Dr. Colin Aspin (U. Hawaii) has requested archival images and other observations of the FU Orionis variable V1647 Ori and the surrounding field over the previous 10 years in support of a study of this star.  Aspin writes that he is hoping to obtain more data with which to create a multi-year light curve of this star to put present-day observations in context of its past behavior.

Special Notice #234: Outburst of FS Aurigae

February 14, 2011: Further to AAVSO Alert Notice 428 (2010 Nov 30), the dwarf nova FS Aurigae appears to be in outburst.  The current outburst was detected simultaneously by P. Lake (Wonga Park, Victoria, Australia) at m(vis)=14.5 on 2011 Feb 14.0969 (JD 2455606.5969), and confirmed shortly after by G. Lubcke (Middleton, WI, USA) at around V=14.4 in time-series observations made simultaneously to the observation of Lake.  Follow-up photometry of this star is encouraged.

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.

Alert Notice 425: Monitoring of HBC 722 and VSX J205126.1+440523 Requested

October 1, 2010: Dr. Colin Aspin (U. Hawai'i) has requested the help of AAVSO observers in performing long-term photometric monitoring of the two new young stellar objects (YSOs) in Cygnus, HBC 722 and VSX J205126.1+440523 (see AAVSO Special Notice #216).  

Special Notice #217: SN 2010hg in NGC 3001

September 2, 2010: We have been notified by Dan Green, Central Bureau for Astronomical Telegrams, that Berto Monard (MLF), Pretoria, South Africa, has discovered a bright supernova (discovered at 15.0, brightened to 14.7 in 24 hours) in NGC 3001. Here are details quoted from CBET 2434 (Green, ed.):

Observation Notification

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