AAVSO International Database

Alert Notice 796: Monitoring requested for 12 dwarf novae in support of HST observations in 2022-2023 (back-up copy)

The target table below is being updated as each target is completed or rescheduled.  -  Elizabeth O. Waagen

Notes:  LL Lyr was not able to be observed due to issues with HST. It has been rescheduled for the 2023-2024 year of this campaign.   -  Elizabeth O. Waagen, October 24, 2023

Please observe LL Lyr nightly in anticipation of upcoming HST observations in September. An Alert Notice will be issued when it has been scheduled.  -  Elizabeth O. Waagen, September 5, 2023

Alert Notice 758: Monitoring requested for 11 dwarf novae in support of HST observations in 2021-2022 (back-up copy)

Note:  RY Ser was scheduled for May and for June but was in outburst or too close to outburst to be a safe target. It may be rescheduled. GP Com observations did take place.  -  Elizabeth O. Waagen, July 5, 2022

GP Com observations will take place April 29-30, 2022; coverage is needed until May 20. See Alert Notice 775.  -  Elizabeth O. Waagen, April 27, 2022

Alert Notice 859: Photometry and spectroscopy requested for bright binaries being observed with CHARA - Revised (backup copy)

Note:  Some of the targets below are being re-assessed for continued coverage. For the present, please continue to observe all targets.  -  Elizabeth O. Waagen, September 30, 2024

The Alert Notice text below has been revised from the original version issued April 18, 2024.  - Elizabeth O. Waagen, April 19, 2024

Alert Notice 841: VY Scl coverage needed now for HST ToO observations (backup copy)

Notes:  VY Scl has brightened nearly to its high state but may turn around again; ongoing observations are requested. - Elizabeth O. Waagen, October 7, 2025

VY Scl  is currently in its low state, and ongoing observations are requested. - Elizabeth O. Waagen, February 4, 2025; May 6, 2025

Alert Notice 785: Monitoring of V452 Vul = HD 189733 requested (backup copy)

Notes: Please continue observations at least through the 2024 observing season.  -  Elizabeth O. Waagen, July 2, 2024

HST observations were postponed. Please continue to monitor V452 Vul as instructed below until further notice.  -  Elizabeth O. Waagen, October 25, 2022

July 5, 2022

Alert Notice 750: T CrB photometry and spectroscopy requested for HST and XMM-Newton observations (backup copy)

Note: Ongoing observations of T CrB are extremely important as the eruption predicted for 2024 draws closer. See HERE for more information.  -  Elizabeth O. Waagen, July 5, 2023, July 2, 2024

Please continue to monitor T CrB until further notice.  -  Elizabeth O Waagen, February 9, 2023

Alert Notice 752: Rare Outburst of Recurrent Nova RS Ophiuchi (backup copy)

Notes: Post-outburst observations continue to be valuable and of interest. Please continue to observe RS Oph.  -  Elizabeth O. Waagen, July 2, 2024, September 30, 2024, February 4, 2025

Please continue to observe RS Oph, although the 2021 outburst is over. It returned to a fainter magnitude than before the outburst, so ongoing follow-up observations will be very valuable.  -  Elizabeth O. Waagen, April 4, 2022

August 9, 2021