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cataclysmic variable

Special Notice #321: Observations critical tonight for SDSS J093249.57+472523.0

January 10, 2013: Further to AAVSO Alert Notice 471 ( and AAVSO Special Notice #319 (, tonight's observations of SDSS J093249.57+472523.0 will be critical, as sometime tomorrow (January 11) the scheduling team will make the final decison about going ahead with the HST COS observations planned for

Special Notice #319: HST COS observing SDSS J093249.57+472523.0 2013 January 11-12

January 4, 2013: Further to AAVSO Alert Notice 471 ( and AAVSO Special Notice #317 (, HST COS is scheduled to observe the U Gem-type cataclysmic variable

                    SDSS J093249.57+472523.0   on  2013 January 11 21:18:00 through January 12 02:57:19 UT

Special Notice #311: HST COS to observe CW Mon 2012 November 30 - December 1

November 20, 2012:  The HST COS far ultraviolet observations of the dwarf nova CW Mon will be taking place 2012 November 30 20:54:49 through 2012 December 1 02:26:15 UT (AAVSO Special Notice #309,

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.

Special Notice #299: Observations needed TODAY of SDSS J164248.52+134751.4

October 10, 2012: Dr. Boris Gaensicke (leader of the consortium observing CVs with the HST COS instrument; see AAVSO Alert Notice 471 and AAVSO Special Notice #297 for details and instructions) writes with an urgent message:
"STScI would like an update on SDSS J164248.52+134751.4 by ~16UT TODAY (2012 October 10), when the star is not easily visible for most of our observers. Any observations from Europe early this evening will be most welcome."


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