For 10 years, the Hubble Space Telescope has been gathering details about Andromeda, our neighboring galaxy, located 2.5 million light-years away from the Milky Way. The result’s a 2.5 billion pixel mosaic (a pixel is the smallest unit of shade data in a digital picture) containing 200 million brilliant blue stars hotter than the Sun, with different galaxies and cosmic mud within the background. This detailed overview reveals somewhat extra in regards to the historical past of Andromeda, also called M31. In the south of the galactic disk there are indicators of a merger with smaller galaxies, equivalent to M32, which was absorbed by Andromeda two to a few billion years in the past. Andromeda, a spiral galaxy just like the Milky Way, will be seen with the bare eye from the Northern Hemisphere on a transparent day, showing like a grey oval with a diameter roughly six instances bigger than the total Moon. It is essentially the most distant object within the Universe that may be seen with no telescope (Astrophysical Journal, January 16; Universe Today, January 20).
NASA, ESA, B. Williams (University of Washington)The most detailed image of Andromeda, displaying 200 million stars hotter than the SunNASA, ESA, B. Williams (University of Washington)