dwarf nova

Special Notice #329: Critical time for CV Campaign HST/COS target SDSS J100515.38+191107.9

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

Special Notice #326: Next HST/COS target is SDSS J100515.38+191107.9

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

Special Notice #324: LT Eri (SDSS J040714.78-064425.1) is next HST COS target

January 21, 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 dwarf nova LT Eri (SDSS J040714.78-064425.1). HST COS is scheduled to observe it:

                                           LT Eri  2013 January 24 03:55:46 through 06:29:15 UT

Special Notice #322: CU Vel is next HST COS target

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

Alert Notice 475: Monitoring of the dwarf nova U Geminorum in support of HST observations

December 22, 2012: As announced by Dr. Matthew Templeton (AAVSO) in AAVSO Special Notice #316 (www.aavso.org/aavso-special-notice-316), Dr. Michael Shara (American Museum of Natural History, Columbia University) has requested dense coverage of the dwarf nova U Gem in support of HST Cosmic Origins Spectrograph (COS) observations scheduled for now through February 20, 2013.

Special Notice #316: Monitoring of the dwarf nova U Geminorum in support of HST observations

December 17, 2012: The AAVSO requests enhanced nightly monitoring of the dwarf nova U Gem in support of target-of-opportunity observations with HST's Cosmic Origins Spectrograph. These observations were requested by Dr.