Messier 31
Object Information:

Messier 31 - The Andromeda Galaxy

Name - Messier 31, The Andromeda Galaxy
Constellation - Andromeda
Distance - approximately 2,000,000 light years

The Andromeda Galaxy is a naked eye object at moderately dark locations. It can easily be seen with binoculars as a bright fuzzy patch between the constellations Cassiopeia and Pegasus. At a distance of 2 million light years, the Andromeda Galaxy is the nearest large spiral galaxy to our own Milky Way. This galaxy is thought to be very similar in size and shape to the Milky Way. It is approximately 150,000 light years in diameter with a mass of approximately 200-300 billion suns.

The two companion galaxies of M31 can also be seen in this photograph. M32 is the white smudge just above the plane of the galaxy and to the left of center. M32 is estimated to be approximately 6,000 light years in diameter. M110 can be seen directly below M31. Both are elliptical galaxies and are gravitationally bound to M31.

Image date:

September 19, 2009

Exposure Information:

RGB image - 1.5 hours per color channel.

Imaged at:

Mt. Laguna, San Diego County, California


Optics - Takahashi Epsilon 160 f/3.3 astrograph
Mount - Astro-Physics AP 1200 GTO
Camera - SBIG STL-11000 M