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Alert Notice 702: TCP J21040470+4631129 to be observed with HST

Note: The HST observations of  TCP J21040470+4631129 have been postponed due to the target's going into (super)outburst on 2020 March 31. The observations will be rescheduled at a later time and this notice will be updated accordingly; a new Alert Notice may also be issued. However, photometry is still requested (please see AAVSO Alert Notice 703 for details).  -  Elizabeth O. Waagen, April 2, 2020


March 27, 2020

Alert Notice 699: V386 Ser HST observing schedule revised

Note: The HST observations of V386 Ser will take place Friday, 2020 February 28. Positive observations are CRITICAL for the nights of Feb 26-27 and 27-28. Please report observations immediately. - Elizabeth O. Waagen, 2020 February 26

February 14, 2020

Alert Notice 698: V386 Ser to be observed with HST

Note: Please see AAVSO Alert Notice 699 for updated HST schedule and observing instructions. - Elizabeth O. Waagen, February 14 2020.

February 7, 2020

Alert Notice 695: HST to observe V694 Mon (MWC 560)

Note: Note: The Chandra observations took place, and Dr. Karovaska requests continued monitoring of V694 Mon (MWC 560) until further notice.  -  Elizabeth O. Waagen, 17 April 2020

Alert Notice 689: R Aqr monitoring needed in support of HST and Chandra observations

Note:  Continued observations in all bands (particularly B and V) and spectroscopy are extremely important. Please continue nightly observations until further notice.  -  Elizabeth O. Waagen, 31 January 2020

Note: The exact schedules for the Chandra and HST observations of R Aqr (Alert Notice 689) are as follow:

Chandra (UT)  Note that this date is EARLIER than given in Alert Notice 689.
12 Jan 2020 00:13:21.409 - 12 Jan 2020 14:06:41

Alert Notice 675: V386 Ser - second rescheduling of HST observations

Note: Dr. Szkody informs us that the HST observations of V386 Ser have been scheduled for 2019 Aug 15  22:04:49 UT - Aug 16 00:31:52 UT. The critical night is August 14 - please report your observations of V386 Ser as soon as possible after you make them so that HST can be notified in time to make the go-nogo decision. - Elizabeth O. Waagen, August 6, 2019

August 2, 2019

Alert Notice 669: V386 Ser HST observations rescheduled

August 2, 2019: These HST observations of V386 Ser have been rescheduled to August 15-16. Please see AAVSO Alert Notice 675 for further information and updates.  - E. O. Waagen, AAVSO

Alert Notice 667: V386 Ser to be observed with HST

Updated May 24, 2019: Dr. Paula Szkody informs us that the exact time for the HST observation of V386 Ser has been scheduled for 2019 May 30 04:36-10:15 UT. This is the night of May 29/30 for US observers. Thus, the critical night will be May 28/29 (Wednesday night)  to get a measurement to HST so they can proceed to the observation. It will be essential to have positive observations from this night to satisfy the HST planners, so observers with suitable equipment are urged to obtain positive measurements of this faint star.

Alert Notice 651: Monitoring of T Pyx needed for HST observations

September 27, 2018: Dr. Ed Sion (Villanova University) requests AAVSO observers' assistance in monitoring the recurrent nova T Pyx, beginning immediately, in support of upcoming HST observations.

The HST COS observations have been scheduled to take place during the window of 2018 October 4 - 6. It is essential to know the status of T Pyx in order for the HST team to safeguard the instrumentation and make a final decision about approving the COS observations.

Alert Notice 628: HST observations scheduled for SDSS J153817.35+512338.0

March 29, 2018: Further to AAVSO Alert Notice 618, Anna Pala (Ph.D. candidate, University of Warwick) informs us that the date and time of the HST observations planned for the faint polar cataclysmic variable SDSS J153817.35+512338.0 have been set for

2018 April 6 17:33:26 - 21:33:19 UT


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