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dwarf nova

Special Notice #304: HST COS observations of SDSS J001153.08-064739.1 scheduled

October 31, 2012:  Further to AAVSO Alert Notice 471 (Gaensicke, Patterson, and Henden) and AAVSO Special Notice #298, the HST COS (Cosmic Origins Spectrograph) far ultraviolet observations of THE NEXT TARGET from the list, the dwarf nova-type cataclysmic variable

                           SDSS J001153.08-064739.1,

have been scheduled for 2012 November 9 20:42:29 UT through 2012 November 10 04:57:33 UT.

Special Notice #303: VLBA and e-MERLIN observations of SS Cyg underway

October 31, 2012:  The cataclysmic variable SS Cyg is beginning to decline from what appears to be a narrow outburst, and was at visual magnitude 9.1 on 2012 October 30, according to observations in the AAVSO International Database.

Alert Notice 459: Monitoring of RU Peg requested for Swift observations

6 June 2012: Dr. Koji Mukai (Universities Space Research Association/NASA Goddard Space Flight Center) has requested AAVSO observers' assistance in monitoring the SS Cyg-type dwarf nova RU Peg in support of target-of-opportunity observations with the NASA Swift satellite during an outburst.

His observations will be targeted during the rise to outburst and during late decline from outburst. Thus, your prompt notification to AAVSO Headquarters of activity in RU Peg will be crucial to the success of this campaign.

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 #245: Outburst of SV Ari

August 2, 2011:  SV Ari, a suspected WZ Sge star, has gone into outburst.  Rod Stubbings posted a 15.0 magnitude estimate on 110802.788 that has been confirmed by Gianluca Masi.  Gary Poyner says:

"Discovered by M & G Wolf on Heidelberg plates taken in November 1905 at mag 12.0p.  Kimpel & Jansch reported a possible sighting in September 1943, but this was not confirmed.  Nothing has been seen since."

Special Notice #239: Dwarf Nova in Pegasus (PNV J21095047+1348396)

May 31, 2011: IAU Central Bureau for Astronomical Telegrams Electronic Telegram CBET 2731 (Daniel W. E. Green, ed.) announces the discovery by K. Itagaki, Yamagata, Japan, of a dwarf nova in Pegasus (reported by H. Yamaoka, Kyushu University, Japan) on 2011 May 24.672 UT at unfiltered CCD magnitude ~11.5. Spectroscopy by Akira Arai, Koyama Astronomical Observatory, Kyoto Sangyo University, Japan, on 2011 May 25.67 UT, and by D. D. Balam, Dominion Astrophysical Observatory, National Research Council of Canada, M. L.

Special Notice #233: Bright outburst of the cataclysmic variable SDSS J133941.11+484727.5

February 7, 2011: The star SDSS J133941.11+484727.5 has been reported in outburst by Jeremy Shears (Bunbury, UK).  Shears reports this star at magnitude 10.4 on 2011 February 7.919 (JD 2455600.419).  This is approximately 7 magnitudes above quiescence, which suggests a superoutburst of an SU UMa star or a WZ Sge-like outburst.  Gary Poyner (Birmingham, UK) confirms this outburst, estimating the star at 10.5 on February 7.959 (2455600.459).


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