Andromeda is a spectacular spiral galaxy. On a dark night, it is clearly visible to the naked eye as a faint, cloudy region. The galaxy appears
in written records dating back as
far as tenth-century Persia. In
A.D. 905 the Persian astronomer Al Sufi described it as ΓÇ£the little cloud.ΓÇ¥ Most galaxies are lucky to have one name; Andromeda has three. It is most commonly known as the Andromeda Galaxy, since it
appears in the constellation of
that name. The designation M31 dates back to the eighteenth-century astronomer Charles Messier, who listed the galaxy as the 31st in his catalogue of interesting objects. And in 1888 J.L.E. Dreyer published A New General Catalogue of Nebulae and Clusters of Stars, in which he assigned Andromeda the number
