Alert Notice 454: Monitoring of CH Cyg requested for Chandra and HST observations

Campaign continued through 2018. Also, campaign has been updated in Special Notice #417 (20160603), Special Notice #320 (20130109), Special Notice #294 (20120911), Special Notice #268, (20120323 ), and Special Notice #267 (20120315).

March 2, 2012:  Dr. Margarita Karovska, Harvard-Smithsonian Center for Astrophysics, has requested visual and photometric observations of the symbiotic variable CH Cyg in preparation for and support of Chandra and HST observations scheduled for later in March 2012. Dr. Karovska's observations will be a followup investigation of the central region of CH Cyg and its jet that was discovered a couple of years ago. AAVSO observations are requested in order to monitor the state of the system and correlate with the satellite observations.

Visual observations and CCD/PEP observations in all bands - U through J and H - are requested. Daily observations now through April 2012 and high-speed photometry through March would be appreciated. CH Cyg is currently at visual magnitude 7.7.

Halpha, OIII region, and optical spectroscopy are also requested.

More details on the exact dates and times of the satellite observations will be announced when they become available, but daily monitoring should begin now.

Coordinates: RA 19 24 33.07  Dec. +50 14 29.1 (J2000.0)

Finder charts may be plotted using the AAVSO International Variable Star Plotter (VSP) at

Please report observations to the AAVSO International Database as CH CYG.

Many thanks for your valuable contributions to this interesting research!

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


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