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A 4-year light curve for T Cephei

T Cephei is a Mira type variable - a red giant star that varies in brightness due to pulsations in its cool outer layers.

Its extreme brightness range is between magnitudes 5.4 and 11.0 although, as this light curve shows, it hardly ever hits these upper and lower limits. The average interval beteen maxima is 389 days - just under 13 months.

The 2016 maximum  was predicted to occur at the end of May. Observations indicated however that peak brightness actually occurred in early May. The next maximum is predicted to occur in June 2017.

A distinctive feature in the light curve of T Cephei is the pause near magnitude 8.0 during the rise towards maximum. This "pause" has become increasingly prolonged in recent years. Whereas it used to last for a couple of weeks, the latest pause persisted for nearly three months.

Additional information about T Cephei, including finder charts, can be found in  this guide

Added by:  Tracie Heywood