AAVSO Special Notice #258: Request for monitoring of SS Cygni in support of European VLBI radio observations

October 13, 2011: As mentioned in AAVSO Alert Notice 445 on August 19, 2011, Dr. James Miller-Jones (International Centre for Radio Astronomy Research, Curtin University, Perth, Western Australia) and colleagues have a multiwavelength campaign on the dwarf nova SS Cyg underway as a follow-up to their very successful multiwavelength campaign on SS Cyg in 2010 April (see AAVSO Special Notices #204 and 206 and the related information page).

Shortly after we announced the follow-up campaign in August, SS Cyg went into outburst and, thanks to your excellent coverage and immediate notification to Headquarters, Dr. Miller-Jones and colleagues were able to obtain excellent observations.

They have more time available, however, and would like to observe SS Cyg again.


with subsequent 2011 windows of November 23-24 and December 14-15.

Dr. Miller-Jones says, "Ideally we would like to know the state of SS Cyg (particularly whether or not it is going into outburst) a few days before each of these dates, to give us time to alert the schedulers and get on the telescope if appropriate. We would be extremely grateful for any assistance the AAVSO could provide.”

SS Cyg is the class prototype of the dwarf novae, and the brightest dwarf nova in our skies. In quiescence, SS Cyg varies around V=12.0, and will typically reach V=8.0 at maximum, although anomalous weak outbursts are sometimes seen. SS Cyg last went into outburst 2011 August 24 (JD 2455797.6139, 11.3, R. King; 2455797.9875, 11.2, H. Matsuyama); the outburst was a narrow one, lasting 10 days. The next outburst may occur at any time. Observations brighter than m(vis)=11.0 should be reported as quickly as possible.

Observers are asked to increase their monitoring of SS Cyg at least through December. Please report all observations as soon as is practical. In the event of an outburst, please report your observations as quickly as you can via WebObs, and also notify Dr. Matthew Templeton and Elizabeth Waagen at AAVSO Headquarters (matthewt@aavso.org, eowaagen@aavso.org). Visual magnitude estimates are a fast and effective means of monitoring SS Cyg; CCD observations are also useful, but please reduce your frames and report your data as soon as possible following an observing run. CCD time-series are not specifically required for this project.

Coordinates for SS Cyg:  RA 21:42:42.79  Dec +43:35:09.9  (J2000.0)

Charts for SS Cyg may be plotted using AAVSO VSP: http://www.aavso.org/vsp

This campaign is being followed on the AAVSO Observing Campaigns page. For more information on this project, please see Dr. Miller-Jones' website: http://www.astro.virginia.edu/xrb_jets

Please promptly report all observations to the AAVSO International Database using the name "SS CYG".

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


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