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M31

The Andromeda Galaxy (also known as Messier 31, M31, or NGC 224; often referred to as the Great Andromeda Nebula in older texts) is a spiral galaxy approximately 2.5 million light-years away[4] in the constellation Andromeda. It is the nearest spiral galaxy to our own, the Milky Way. As it is visible as a faint smudge on a moonless night, it is one of the farthest objects visible to the naked eye, and can be seen even from urban areas with binoculars.
Andromeda is the largest galaxy of the Local Group, which consists of the Andromeda Galaxy, the Milky Way Galaxy, the Triangulum Galaxy, and about 30 other smaller galaxies. Although the largest, it may not be the most massive, as recent findings suggest that the Milky Way contains more dark matter and may be the most massive in the grouping. However, recent observations by the Spitzer Space Telescope revealed that M31 contains one trillion (10^12) stars, greatly exceeding the number of stars in our own galaxy.2006 estimates put the mass of the Milky Way to be ~80% of the mass of Andromeda, which is estimated to be 7.1×10^11 solar masses. However, a study released by the Harvard-Smithsonian Center for Astrophysics on January 5, 2009,concluded that earlier estimates were erroneous and that Andromeda and the Milky Way are about equal in size and mass.
At an apparent magnitude of 4.4, the Andromeda Galaxy is notable for being one of the brightest Messier objects, making it easily visible to the naked eye even when viewed from areas with moderate light pollution. It appears quite small without a telescope because only the central part is bright enough to be visible, but the full angular diameter of the galaxy is seven times that of the full moon.
From wikipedia

m31_sd_kelling2010t.jpg
Bagged by: Simon Dawes click on the thumbnail to show a larger image
Method: ED80 and Canon 400D taken at Kelling Heath Star Party 2010
Please note that all pictures are copyrighted and may not be used without the explicit permission of the owner.
Click on the image for a high resolution version

kelling201009-06t.jpg
Bagged by: Martin Crow click on the thumbnail to show a larger image
Method: ED80 and Canon 400D taken at Kelling Heath Star Party 2010
Please note that all pictures are copyrighted and may not be used without the explicit permission of the owner.
Click on the image for a high resolution version

m31_JT02t.jpg
Bagged by: Julian Tworek
Instrument: AstroTrac Canon 100-400 lens @ 200mm ISO 1600 13 x 120s modified 20D
Details:Taken at Kelling Heath Star Party 2010
Click on the image for a high resolution version

m31JT01t.jpg
Bagged by: Julian Tworek
DSLR Short Focus Refractor
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m31_mc01.jpg
Bagged by: Martin Crow
Please note that all pictures are copyrighted and may not be used without the explicit permission of the owner.



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Page edited 11 times. Last edit by - SimonTelescopium SimonTelescopium on Nov 23, 2010 2:07 pm. This site contains 560 pages
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