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Special Notice #422: GDS_J1701281-430612 HST observations scheduled

September 30, 2016: Further to AAVSO Alert Notice 551, Dr. Mark Reynolds (University of Michigan) informs us that the cataclysmic variable GDS_J1701281-430612 will be observed by the HST/COS on

07 Oct 2016 at 00:23:57 UT

Alert Notice 551: GDS_J1701281-430612 monitoring for HST observations

Note added September 27, 2016: Dr. Reynolds adds the following: "Visual observations would be useful in setting a baseline and understanding how variable the source is in a relative sense at the time of our HST observation."

September 20, 2016: Dr. Mark Reynolds (University of Michigan) and colleagues have requested AAVSO assistance in monitoring the cataclysmic variable GDS_J1701281-430612 in support of HST/COS observations scheduled for early October.

Special Notice 410: Upcoming HST observations of V5668 Sgr

Note: this text is slightly different than the emailed version.  No technical information was changed.

Alert Notice 533: Coverage of V5668 Sgr (Nova Sgr 2015 No. 2) requested in support of HST spectroscopy

October 30, 2015: Dr. Peter Kuin (Mullard Space Science Laboratory, University College London) and colleagues in the Swift Nova group have requested AAVSO observers' assistance in multicolor monitoring of V5668 Sgr (Nova Sgr 2015 No. 2, see AAVSO Alert Notices 512, 519) in support of an upcoming spectroscopic observation with the Hubble Space Telescope Imaging Spectrograph (STIS).

Alert Notice 526: Monitoring of LS IV -14 116 in support of upcoming satellite observations

August 20, 2015Prof. Simon Jeffery (Armagh Observatory; Trinity College Dublin) has requested photometric monitoring of the pulsating helium and zirconium-rich hot subdwarf LS IV -14 116 in support of upcoming HST and VLT/UVES spectroscopy. AAVSO observations will supplement photometry due to be obtained with the SAAO 1.0-m and IAC 0.8-m telescopes from 18 August to 2 September 2015. Photometry is requested beginning immediately through 2 September.

Alert Notice 522: V404 Cyg HST multiwavelength observations scheduled

Correction: In the text below, the date of the detection by the Swift satellite was incorrectly given as 2015 June 16.77197 UT. The correct date is 2015 June 15.77197 UT.

Our sincere apologies for this error!

July 1, 2015:

Special Notice #403: GW Lib HST schedule set

April 16, 2015: Further to AAVSO Alert Notice 513, Dr. Paula Szkody (University of Washington) informs us that the HST observations for the cataclysmic variable GW Lib have been scheduled for

2015 April 22 04:04:36 - 09:00:06 UT.

Alert Notice 513: Request for observations of GW Lib in support of HST observations

March 18, 2015: Dr. Paula Szkody, University of Washington, has requested our help in monitoring the cataclysmic variable GW Lib for upcoming Hubble Space Telescope observations, scheduled to be made during the window 2015 April 22-25 UT. Dr. Szkody also observed this object with HST in March 2011 and March 2010 (see AAVSO Alert Notices 433 and 417, respectively).

Special Notice #199: Request for monitoring of GW Lib in support of HST Observations

March 8, 2010: Further to Alert Notice 417, the AAVSO requests intensive monitoring observations of the cataclysmic variable GW Librae beginning immediately (2010 March 9.0 UT; JD 2455264.5) and continuing through 2010 March 12.5 (2455268.0). These observations are in support of the Hubble Space Telescope Cosmic Origins Spectrograph observations of GW Lib planned for 2010 March 11 UT. Space Telescope ground controllers will need to know that GW Lib is fainter than V=15 in order to proceed with the planned observations.


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