Alert Notice 692: V694 Mon (MWC 560) to be observed with Chandra

Note: Note: Observations of V694 Mon are scheduled for 11 March 2020 with HST, and for 22 March 2020 with XMM. Please continue to observe as indicated in Alert Notice 695 but with the high-intensity coverage taking place March 9 through March 14 and March 19 through March 25.  -  Elizabeth O. Waagen, 6 March 2020

Note: Additional satellite observations of V694 Mon are taking place, so please continue nightly observations until at least mid-March 2020. - Elizabeth O. Waagen, 27 February 2020

January 22, 2020

AAVSO Forum threads (scroll to the bottom of a thread for latest posts):
  -   Campaigns and Observing Reports:
  -   Spectroscopy:

Further to AAVSO Alert Notice 678, Dr. Margarita Karovska (Center for Astrophysics|Harvard & Smithsonian) informs us that the symbiotic system V694 Mon (MWC 560) is currently scheduled to be observed with the Chandra X-ray satellite during the week (UT) of 27-Jan-2020 to 03-Feb-2020.

When the exact time is known, this Alert Notice and the related forum threads will be updated. Observers should monitor these sources for updates.

Dr. Karovska requests nightly observations (UBVR photometry and spectroscopy), and, if possible, high-speed photometry (U and B). Visual observations are also encouraged.

Recent observations of V694 Mon in the AAVSO International Database show the system at 8.787 V +/-0.013 on 2020 Jan. 19.9238 UT (C. Gualdoni, Como, Italy), and at visual magnitude 8.9 on 2020 Jan. 20.8760 UT (G. Poyner, Birmingham, England). Its range is 8.64-12.2 V.

Spectroscopy observations should focus on the [OIII] 5007A line and the Halpha line regions. Spectroscopy reports (including plot, if possible) should be sent to Dr. Karovska ( and submitted to the AAVSO Spectroscopy Database (

Coordinates: R.A. 07 25 51.28  Dec. -07 44 08.2 (2000.0)

AAVSO finder charts for V694 Mon with comparison stars may be generated using the AAVSO Variable Star Plotter (VSP).

Please submit your optical observations to the AAVSO International Database using the name V694 MON.

 This AAVSO Alert Notice was compiled by Elizabeth O. Waagen.

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