M31 - the Andromeda Galaxy is the closest major galaxy to our own Milky Way. Located about 2.5 million light-years away, it is the largest galaxy in the Local Group of 54 galaxies that orbit a gravitational center between our Milky Way and M31. When the photons we see today left their source in Andromeda, the first members of the Homo genus had not yet appeared, and it would be another 2.25 million years before modern humans evolved. Approximately 220,000 light-years across, the large, spiral galaxy contains at least one trillion stars. Though some people claim to see the Triangulum or M81 & M82 which are more distant, the Andromeda galaxy is the furthest easy naked eye object in semi-dark skies. We'll collide with M31 in about 4.5 billion years, so mark that on your calendar.

Also in the field are M31 friends M110, M32, and NGC 206.

In the lower left of the image, M110 orbits the Andromeda galaxy as a dwarf elliptical galaxy. There appears to be recent star formation, but no supermassive black hole at its center. It is the final item in Messier's catalog. Though he never included it himself, his drawings suggest he observed it first on August 10th, 1773.

In the top center is dwarf elliptical galaxy M32. Also a satellite of M31, it is slightly more distant at 2.65 million light years away. Discovered in 1749 by French astronomer Guillaume Le Gentil, it is old and therefore has no current star formation and very little dust or blue stars.

Nestled in the top left spiral arm of M31 is NGC 206. It is a bright star cloud located in the Andromeda galaxy and is one the largest star-forming regions in the Local Group. With more than 300 mag 3 stars, it was discovered by Edwin Hubble. Originally cataloged as a star cluster, it is actually two distinct star-forming regions separated by interstellar dust.

Acquisition:

Imaged on 11/29/16, 12/13/16, 12/18/16 & 12/19/16 from Lake St Louis, MO

Integration: 8 hours (LRGB)

Luminance: 24x600s @ 1x1 (240')

R/G/B: 16/16/16 x 300s @ 2x2 (80'/80'/80')

Equipment:

Scope: William Optics GTF 81 5 element refractor (535mm focal length)

Upgraded with Moonlite CF focuser with motor

Imager: QHY9Ms with Olivon OAG and QHYCFW2-s filter wheel

Guidecam: ASI120MM

Filters: Baader LRGB

Mount: Orion Atlas EQ-G

Processing and Software

Guiding with PHD2

Acquisition with Sequence Generator Pro

Integration and processing with PixInsight 1.8

M31 - Andromeda Galaxy: https://www.flickr.com/photos/mpusatera/31846296555/sizes/l

Annotated image: https://www.flickr.com/photos/mpusatera/31808478876/sizes/l

Astrobin: http://astrob.in/277153/0/