HST

Special Notice #209: Nightly monitoring of TW Hya in support of HST observations

May 17, 2010: Dr. Michael Sitko (U. Cincinnati) requests observations of the young stellar object TW Hya in support of upcoming Hubble Space Telescope observations. TW Hya is believed to be a T Tauri star that varies between magnitudes 10.5 and 12.2. TW Hya will be observed with the HST STIS instrument as part of a larger program to study the properties of potentially planet-forming disks around young stars. The star will be observed in the ultraviolet to search for time-variability in the gas in the inner accretion disk.

Special Notice #385: SBS 1108+574 HST/COS observations crucial NOW

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!

Special Notice #384: SBS 1108+574 HST/COS obs next week

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

Alert Notice 501: Monitoring requested for HST/COS observations of SBS 1108+574

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.

Special Notice #382: SDSS J100658.40+233724.4 observations crucial now

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.

Special Notice #381: HST/COS observations of SDSS J100658.40+233724.4

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)

Special Notice #376: HST observations of U Gem scheduled for December 6

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:

Alert Notice 195: Symbiotic stars AND Cataclysmic variables AND 1510+83 Z Ursae Minoris

THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
25 Birch Street, Cambridge, MA 02138 USA
BITNET:  aavso@cfa     SPAN:  cfa::aavso
INTERNET:  aavso@cfa.harvard.edu
Tel. 617-354-0484       FAX 617-354-0665

AAVSO ALERT NOTICE 195 (November 23, 1994)

SYMBIOTIC STARS

Alert Notice 197: Observations of cataclysmic variables for Astro-2, EUVE, Voyager, and ASCA satellites AND Reminder regarding outburst of 0749+22 U Gem

THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
25 Birch Street, Cambridge, MA 02138 USA
BITNET: aavso@cfa SPAN: cfa::aavso
INTERNET: aavso@cfa.harvard.edu
Tel. 617-354-0484 FAX 617-354-0665

AAVSO ALERT NOTICE 197 (January 27, 1995)

OBSERVATIONS OF CATACLYSMIC VARIABLES FOR ASTRO-2, EUVE, VOYAGER,
AND ASCA SATELLITES