Newscenter Update: Hubble Finds Giant Halo Around the Andromeda Galaxy

May 7, 2015 Get larger image formats   Find the entire Hubble News archive, image galleries, and much more at hubblesite.org Stay Connected   Hubble Finds Giant Halo Around the Andromeda Galaxy The Andromeda galaxy is our Milky Way's nearest neighbor in space. The majestic spiral of over 100 billion stars is comparable in size to our home galaxy. At a distance of 2.5 million light-years, it is so close to us the galaxy can be seen as a cigar-shaped smudge of light high in the autumn sky. But if you could see the huge bubble of hot, diffuse plasma surrounding it, it would appear 100 times the angular diameter of the full Moon! The gargantuan halo is estimated to contain half the mass of the stars in the Andromeda galaxy itself. It can be thought of as the "atmosphere" of a galaxy. Astronomers using Hubble identified the gas in Andromeda's halo by measuring how it filtered the light of distant bright background objects called quasars. It is akin to seeing the glow of a flashlight shining through a fog. This finding promises to tell astronomers more about the evolution and structure of one of the most common types of galaxies in the universe. RELEASE LINKS: See full release More Images Fast Facts This news release and its supporting materials are permanently achived at: http://hubblesite.org/newscenter/archive/releases/2015/15/ You are receiving this email because you are subscribed to the Inbox Astronomy mailing list, which sends notices in HTML whenever there is a new Hubble Space Telescope image, product, or news update. If you would like to unsubscribe or change your email preferences, please go to: http://hubblesite.org/newscenter/hubble_on_the_go/inbox_astronomy/