Milky Way

The Milky Way is the galaxy that contains our Solar System.  Its name “milky” is derived from its appearance as a dim glowing band arching across the night sky in which the naked eye cannot distinguish individual stars. The term “Milky Way” is a translation of the Latin via lactea, from the Greek  (galaxias kyklos, "milky circle").  From the Earth, the Milky Way appears as a band because its disk-shaped structure is viewed from within the Galaxy. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. Up until the 1920s, most astronomers thought that all of the stars in the universe were contained inside of the Milky Way.  Source