COS

May 13, 2014: The HST/COS observations of the cataclysmic variable SBS 1108+574 described in AAVSO Alert Notice 501 and Special Notice #384 are scheduled for 2014 May 16 06:19:04 - 15:16:56 UT.

Your observations TONIGHT AND PARTICULARLY TOMORROW NIGHT ARE CRUCIAL!

May 9, 2014: The HST/COS observations of the cataclysmic variable SBS 1108+574 described in AAVSO Alert Notice 501 have been pushed back a few days. The new exact time of the observations is:

                 SBS 1108+574      2014 May 16 06:19:04 - 15:16:56 UT

April 29, 2014: Dr. Peter Garnavich (University of Notre Dame) and Dr. Paula Szkody (University of Washington) have requested the help of AAVSO observers in monitoring the cataclysmic variable SBS 1108+574 (= CSS 120422:111127+571239) in support of upcoming Hubble Space Telescope observations. The HST COS (Cosmic Origins Spectrograph) will be carrying out far-ultraviolet spectroscopy of this target on 2014 May 12-13 UT.

March 17, 2014: HST/COS is scheduled to observe the the U Gem-type dwarf nova
SDSS J100658.40+233724.4 this Thursday. Observations are scheduled for:

SDSS J100658.40+233724.4 2014 March 20 05:35:00 through 14:17:27 UT

The scheduling team will likely make their final decision early WEDNESDAY (March 19), so your observations are essential tonight and tomorrow night.

March 5, 2014: HST/COS are being scheduled for the U Gem-type dwarf nova SDSS J100658.40+233724.4, the 40th and final target of the major CV observing campaign organized in 2012 by Drs. Boris Gaensicke, Joseph Patterson, Arne Henden, and 13 other astronomers (see AAVSO Alert Notice 471 and note below). A precise time will be announced later, but the scheduled HST observing window is:

SDSS J100658.40+233724.4  2014 Mar. 20 or 21 UT (to be determined)

December 2, 2013: Further to AAVSO Special Notice #318 (M. Templeton) and AAVSO Alert Notice 475 (E. Waagen), Dr. Michael Shara (American Museum of Natural History) informs us that HST/COS observations of the dwarf nova U Gem have been scheduled for 2013 December 6 UT (one day earlier than originally indicated in the December 2 posting to the AAVSO forums). The observations will take place:

Edward Smith (STScI) has requested nightly photometric monitoring of the symbiotic star AG Draconis during the period 2009 August 2, and tentatively scheduled to continue through mid-September 2009.