It was the first compilation of bright galaxies in the northern and southern sky.
The catalog contains position, brightness, size, and Hubble classification of the galaxies.
For the next 60 years, astronomers referred to this catalog as a primary source for information about redshifts and galaxy types.
[3] An important finding from this research was that the galaxies were not evenly distributed (they violated the isotropy assumption) in that the northern hemisphere contained more galaxies than the southern hemisphere.
[6] In 1981, Allan Sandage and Gustav Tammann published an updated version known as the Revised Shapley-Ames Catalog (RSA).