symbiotic variable

Alert Notice 167: The symbiotic star 1810-00 FG Serpentis (AS 296) AND Forthcoming outburst of 0749+22 U Geminorum

THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
25 Birch Street, Cambridge, MA 02138 USA
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AAVSO ALERT NOTICE 167 (February 1, 1993)

THE SYMBIOTIC STAR 1810-00 FG SERPENTIS (AS 296)

Special Notice #429: V694 Mon (MWC 560) spectroscopy requested

May 2, 2017: Further to AAVSO Alert Notice 538, the campaign from 2016 on V694 Mon (MWC 560) has been continued, but with different requirements. Photometry is no longer specifically requested on a regular basis (although ongoing observations that do not interfere with other obligations are welcome). Spectroscopy on a cadence of a week or two is requested to monitor changes in the disk outflow. V694 Mon is presently nearing opposition, but the request for spectroscopy continues until further notice.

Alert Notice 572: AG Dra monitoring requested

April 3, 2017: Dr. Rudolf Gális (Pavel Jozef Šafárik University (Slovakia)) and colleagues have requested AAVSO assistance in observing the symbiotic variable AG Dra. Observations are requested as a follow-up to spectroscopic observations and in order to monitor the system for an anticipated outburst.

Special Notice #417: CH Cygni B and V photometry urgently requested

REQUEST CONTINUED THROUGH 2018

June 3, 2016: Dr. Margarita Karovska (Harvard-Smithosonian Center for Astrophysics) is urgently requesting B and V photometry of the symbiotic variable CH Cyg from now until at least the end of August. Observations made twice a week are sufficient; time series observations are not needed. Spectroscopy would also be very welcome and appreciated.

Alert Notice 538: Observations of V694 Mon (MWC 560) requested for Chandra campaign

February 26, 2016: Dr. Jeno Sokoloski (Columbia University) and Mx. Adrian Lucy (graduate student, Columbia University) have requested AAVSO observations of the jet-driving symbiotic star V694 Mon (MWC 560), which is in outburst, in support of upcoming Chandra observations to investigate the state of the inner accretion disk during this outburst.

The Chandra observations are scheduled (preliminary schedule) for 2016 March 8 (7:17-14:13 UTC) and March 9 (2:20-9:17 UTC).

Special Notice #411: RT Cru observations need to be continued

December 15, 2015: Further to AAVSO Alert Notice 503 and AAVSO Special Notice #409, Dr. Margarita Karovska (Harvard-Smithsonian Center for Astrophysics) urgently requests that multicolor and visual AAVSO observations of the symbiotic variable RT Cru continue.