Elliptical galaxies range in shape from nearly spherical to nearly flat, (E7, one of the flattest types of elliptical galaxies is cigar-shaped) and in size from hundreds of millions to over one trillion stars. Originally, Edwin Hubble thought that elliptical galaxies may evolve into spiral galaxies, but this turned out to be false. Stars found inside elliptical galaxies are much older (and cooler; thus redder) than stars found in spiral galaxies.