Two Million Galaxies . ... APM Survey , Astrophys. ... Oxford U. Explanation: Our universe is filled with galaxies. ... Although distant galaxies move away from each other as the universe expands , gravity attracts neighboring galaxies to each other, forming galaxy groups , clusters of galaxies , and even larger expansive filaments. ... Bright regions indicate more galaxies , while bluer colors denote larger average galaxies. ... NASA Web Site Statements, Warnings, and Disclaimers . ...