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

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 614 : Monitoring of GW Lib to support XMM-Newton observation

February 12, 2018: Dr. Koji Mukai (NASA Goddard Space Flight Center) and colleagues have requested AAVSO observations of the WZ Sge type dwarf nova GW Lib in support of observations with the ESA XMM-Newton spaceobservatory scheduled for

2018 February 17  05:46:41 - 21:36:41 UT

Alert Notice 607: MASTER OT J132104.04+560957.8 photometry urgently needed for XMM observations

December 1, 2017: Dr. Mark Kennedy (Jodrell Bank Centre for Astrophysics, University of Manchester) requests AAVSO observers' assistance in providing optical coverage of the polar MASTER OT J132104.04+560957.8 in support of observations with the XMM-Newton satellite scheduled for this Sunday, 2017 December 3, 08:35:31 UT - 16:38:51 UT.

The XMM-Newton observations themselves will not include an optical component, so photometry provided by AAVSO observers is essential for the interpretation of the X-ray data.

Alert Notice 601: V902 Mon observations needed to support XMM-Newton observation

October 10, 2017: Dr. Hauke Wörpel (Leibniz-Institut für Astrophysik Potsdam (AIP)) has requested AAVSO assistance in obtaining observations of the eclipsing intermediate polar (IP) candidate V902 Mon in support of an XMM-Newton observation scheduled for 2017 October 14, 14:42 UT (duration 43,000s).

AAVSO Special Notice #99: Campaign in support of SS Aurigae observations by XMM-Newton delayed

March 10, 2008: Further to AAVSO Alert Notice 371, we have been informed by Dr. Patrick Godon that XMM-Newton observations of the dwarf nova SS Aurigae have been delayed by the XMM-Newton Science Operations Center. They have not been issued a new date, and so the request for observations in Alert Notice 371 is now cancelled.
Please observe SS Aurigae as part of your normal observing program if you already do so, but increased coverage is not yet required.