SU UMa

February 15, 2007: Dr. Christian Knigge, University of Southampton, England, has requested our assistance in monitoring ten (10) dwarf novae cataclysmic variables as part of a search for radio jet formation during outbursts. Dr. Knigge is attempting to observe a dwarf nova outburst within six hours of the outburst onset using the NRAO Very Large Array (VLA) telescope in New Mexico and the Jodrell Bank MERLIN telescope in the United Kingdom.

March 8, 2013:  Dr. Boris Gaensicke (Warwick University) has requested observations of the currently-outbursting SU UMa-type cataclysmic variable MR UMa in preparation for and support of HST observations scheduled for the week 2013 April 4-7.

February 5, 2013: Further to AAVSO Alert Notice 471 (http://www.aavso.org/aavso-alert-notice-471) and AAVSO Special Notice 330 (http://www.aavso.org/aavso-special-notice-330), HST/COS is scheduled to observe IR Com on:

                                    IR Com   2013 February 8 00:38:46 through 05:57:49 UT

January 29, 2013:  SDSS J100515.38+191107.9 is the upcoming target for the HST/COS CV Campaign (see AAVSO Alert Notice 471 and AAVSO Observing Campaigns page (http://www.aavso.org/observing-campaigns) for details and related Special Notices). Dr. Gaensicke writes:

"We are now entering the critical phase before the HST observations of SDSS1005+1911, scheduled for

January 24, 2013: Further to AAVSO Alert Notice 471 (http://www.aavso.org/aavso-alert-notice-471), the next HST COS target is the SU UMa-type dwarf nova SDSS J100515.38+191107.9. HST COS is scheduled to observe it:

                                          SDSS J100515.38+191107.9 2013 January 31 01:17:09 through 06:24:00 UT

January 14, 2013: Further to AAVSO Alert Notice 471 (http://www.aavso.org/aavso-alert-notice-471) and AAVSO Special Notice #309 (http://www.aavso.org/aavso-special-notice-309), the next HST COS target is the classic SU UMa-type dwarf nova CU Vel. HST COS is scheduled to observe it:

                                                  2013 January 18 06:52:10 through 10:21:40 UT

January 10, 2013: Further to AAVSO Alert Notice 471 (http://www.aavso.org/aavso-alert-notice-471) and AAVSO Special Notice #319 (http://www.aavso.org/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

Discovered in 1908 by L. Ceraski of Moscow, the variable SU Ursae Majoris is located near the tip of the nose of the Great Bear constellation of Ursa Major, about 3° northwest of the bright star omicron Ursae Majoris. SU UMa belongs to the dwarf nova class of cataclysmic variable stars (CVs), being similar to U Geminorum, SS Cygni, and Z Camelopardalis subtypes in terms of the physical system.