A probable RS CVn star which sometimes stops its eclipses ⋆
نویسنده
چکیده
We report the discovery of a new variable star, called S 10947 Aql, as the likely optical counterpart of RX J2009.8+1557. The optical variability pattern as well as the detected X-ray emission suggest that it is a chromospherically active binary of the RS Canum Venaticorum (≡ RS CVn) type. We discovered an occasional disappearance of the eclipsing minima as well as large variations in the eclipse amplitude. We discuss possible causes of this peculiarity.
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