Alert Notice 666: CRTS J105122.8+672528 observations needed urgently

May 14, 2019: Dr. Mark Kennedy (Jodrell Bank Centre for Astrophysics, University of Manchester) is urgently requesting observations of the potential cataclysmic variable CRTS J105122.8+672528 beginning immediately. This object appears to be in outburst, having brightened to V~16.2 from its minimum magnitude of V~18.5-CV~19.

Confirmation of the outburst is requested, as well as observations over the next three weeks. Dr. Kennedy writes: "There have been hints of short term variability becoming stronger during super outburst, which are of interest in classifying this source...Any observations that the AAVSO could provide us over the coming 3 weeks would be of use...[and it if turns out to be a super outburst] any data that the AAVSO can provide which has a short cadence (<60 s) with good S/N (~10) would be incredibly beneficial."

Photometry is requested, in order to obtain as high time resolution light curves as possible, beginning immediately and continuing through June 4. V and CV are both welcome - determining that the variability exists and its nature is more important at present than in which band it is the strongest. Positive visual observations are welcome to help confirm the outburst and to help show the shape of the outburst (in decline fainter-thans below 16 are also welcome).

Coordinates (J2000): R.A. 10 51 22.89  Dec. +67 25 28.3

Charts with a comparison star sequence for CRTS J105122.8+672528 may be created using the AAVSO Variable Star Plotter (VSP). Note that the primary VSX name for this target is CSS 120101:105123+672528; either name may be used.

Please report all observations to the AAVSO International Database using the name CRTS J105122.8+672528.

AAVSO Forums: This campaign is the topic of the AAVSO Campaigns and Observation Reports forum thread and the Cataclysmic Variables forum thread

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


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