The Andromeda Galaxy

384 Words2 Pages
A few galaxies outside the Milky Way are visible in the night sky to the unaided eye. In the 10th century, the Persian astronomer Al-Sufi made the earliest recorded identification of the Andromeda Galaxy, describing it as a "small cloud". The Andromeda Galaxy was independently noted by Simon Marius in 1612. In 1755, Immanuel Kant used the term "island Universe" to describe these distant nebulae. Toward the end of the 18th century, Charles Messier compiled a catalog containing the 109 brightest celestial objects having nebulous appearance. Subsequently, William Herschel assembled a catalog of 5,000 nebulae. In 1912, Vesto Slipher made spectrographic studies of the brightest spiral nebulae to determine their composition. Slipher discovered that

More about The Andromeda Galaxy

Open Document