Andromeda Galaxy Andromeda Galaxy The Andromeda Galaxy (), also known as Messier 31, M31, or NGC 224, is a spiral galaxy approximately 780 kiloparsecs (2.5 million light-years) from Earth, and the nearest major galaxy to the Milky Way. Its name stems from the area of the sky in which it appears, the constellation of Andromeda. The 2006 observations by the Spitzer Space Telescope revealed that the Andromeda Galaxy contains approximately one trillion stars, more than twice the number of the Milky Way's estimated 200 to 400 billion stars. The Andromeda Galaxy's mass is estimated to be around 1.76 times that of the
Places in The Hitchhiker's Guide to the Galaxy the "Guide" has supplanted the "Encyclopedia Galactica" among its more relaxed civilisations, and where in Arthur Dent heads for where "wisdom and truth were to be found" and goes to Hawalius. In the radio series, the Western Spiral Arm of the Galaxy reports that 'the wheel is economically unviable', and in the "uncharted backwaters of [its] unfashionable end", the 'planet' Earth is found. Galactic Sector ZZ9 Plural Z Alpha is a galactic sector containing Earth, Barnard's Star, and probably other nearby systems. The "Plural" designation may indicate probability problems; after Fenchurch disappeared during a hyperspace jump, it was pointed out