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
Don't Panic: The Official Hitchhiker's Guide to the Galaxy Companion Douglas Adams & The Hitchhiker's Guide to the Galaxy") was published in the UK by Titan Books in June 2002, and contains further additional material, this time by M. J. Simpson (). An updated edition was published by Titan Books in October 2003 (). A further edition was published by Titan Books in September 2009 (). Don't Panic: The Official Hitchhiker's Guide to the Galaxy Companion Don't Panic: The Official Hitchhiker's Guide to the Galaxy Companion is a book by Neil Gaiman about Douglas Adams and "The Hitchhiker's Guide to the Galaxy". The book was originally published in 1986 in