This class of variable (named after the discovery of the first star of its type - Mira or Omicron Ceti) consists of red giant stars with late-type spectra whose intrinsic pulsations vary over a long period of time (80 to 1000 days).

This image of T Cephei was taken on the 11th January 2006 at 21:00 GMT (JD 2453747.4). The star has been estimated to have a visual magnitude of 7.2±0.1 at this time and is now fading after having reached a peak in its brightness at the end of October 2005. Note the reddish colour of the star. This square image is 3.2 degrees on a side.

You can look at the details of this observation, the method used to estimate the magnitude and the details of the data reduction.

You can also look at previous observations of this star.