(
Astronomy)
Alpheratz, the alpha, or brightest, star in the constellation Andromeda, and one of the 57 stars of celestial navigation. Alpheratz is a spectroscopic binary - a double star whose secondary star can be seen only with the use of a spectroscope - with an orbital period of roughly 97 days. Its position marks the head of Andromeda. In Greek mythology, Andromeda was the daughter of the queen of Ethiopia who was to be sacrificed to a sea monster as punishment for her mother's vanity. Alpheratz also designates the northeast corner of the Great Square of Pegasus.
Alpheratz has an apparent magnitude of +2.06, and has a blue-white colour. Its spectral class is A0. It's approximately 160 times brighter than our sun. It is to be found on the sky at RA 0h8m and Declination 29° 5'