This picture shows the whole constellation, including milky way starfields and various areas of nebulosity. The red object to the upper left is NGC 7762 (upper/right section) and
Cederblad 214 (brighter section to the left). At the centre bottom of the picture is a large round nebula known as IC 1396.
The bright star immediately above IC 1396 in the picture is mu Cephei, and moving to the left you see a slightly brighter star, Sigma. Moving just up-and-left of that star is a not-quite-as-bright one, Delta. This is an important star for astronomers since it is the prototype "Cepheid Variable". This is a type of star that changes its brightness according to a regular pattern, and the brightness is directly related to the period of variation. Hence the absolute brightness can be determined. Once the absolute brightness of a star is known, the apparent brightness of the star in the sky can be used to calculate the star's distance. Cepheid-type variables have been found all over the sky, even in other galaxies, and are used as "standard candles" to determine their distance.
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