M31 - Andromeda Galaxy

M31 is best known as the Great Andromeda Galaxy. It is the dominant member of the Local Group in which the Milky Way resides. It is 2.5 million light years away and spans approximately 260 light years. It is the farthtest object visible to the naked eye, appearing as a faint patch of light. If the full expanse of the galaxy were visible from Earth, it would span about six times the diameter of the full moon. It has approximately 30 satellite galaxies, most of which are dwarf galaxies. The primary ones visible in the image are M32 (the small eliptical galaxy adjacent to its arms) and M110 (the larger eliptical galaxy below and left). It is believed that interaction between M31 and M32 caused disturbance in its spiral structure. In approximately four billion years, the M31 and the Milky Way are predicted to collide. We are approaching each other at the rate of 70 miles per second.

M31 was once known as the Great Andromeda Nebula. The existence of other galaxies was not known until 1923, when Edwin Hubble identified Cepheid variable stars in M31 and was able to conclude that it lies far outside of the Milky Way.

Telescope: William Optics Star71 refractor
Mount: Orion Sirius
Camera: Canon 650D (Hap Griffin modified); Raw capture @ ISO 800
Exposures: 30 @ 5 min.
Guiding: Orion SSAG on Stellarvue 50mm scope
Processing: Images were focused using Live View. They were converted to TIFF format using Canon Digital Professional. They were reduced, aligned and combined using ImagesPlus. The final image was adjusted in Photoshop. Sharpening and noise reduction were done using Topaz Detail and DeNoise respectively.
Location: My backyard in southeastern Minnesota
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