Probably the most famous galaxy other than the Milky Way, the Andromeda galaxy is our nearest neighbour in space as far as large galaxies are concerned. Andromeda provides a great opportunity to astronomers as it is thought to be very similar to our own galaxy, allowing us to look at galaxies with a different perspective. It is also odd because Andromeda is one of the very few blue shifted galaxies, this blue shifting indicates the galaxy is moving towards us. Astronomers have measured the speed of the galaxy to be about 300km/s and is expected to collide with our own galaxy in approximately 2 billion years.

M31 lies in the constellation of Andromeda and is very easy to find for the amateur astronomer with almost any telescope. Even though the visual magnitude of Andromeda is very bright, +4.4mag, it is quite hard to see anything more than a smudge as it has a very low surface brightness, this is due to the physical size of the galaxy. To view detail visually it is important to have very dark skies and as much contrast as you can get.  Andromeda is probably the most photographed galaxy. M31 lies approximately 0.8Mpc(~2 million light years) away from us and is part of the local group of which m31 and the milky way are the two largest galaxies.

Like the Milky Way, Andromeda Galaxy has satellite galaxies, consisting of 14 known dwarf galaxies. The best known and most readily observed satellite galaxies are M32 & M110.

Based on current evidence, it appears that M32 underwent a close encounter with M31 in the past. M32 may once have been a larger galaxy that had its stellar disk removed by M31, & underwent a sharp increase of star formation in the core region, which lasted until the relative recent past.

M110 also appears to be interacting with M31, & astronomers have found a stream of metal-rich stars in the halo of M31 that appears to have been stripped from these satellite galaxies. M110 does contain a dusty lane, which is a hint for recent or ongoing star formation. This is unusual in elliptical galaxies, which are usually fairly low in dust & gas.

In 2006 it was discovered that nine of these galaxies lie along a plane that intersects the core of the Andromeda Galaxy, rather than being randomly generated. This may indicate a common origin for the satellites.

 This latest image of M31 was taken on 11th August 2010 at 2am....The seeing was good for my part of the world, I could see the Milky Way clearly as it crossed the centre of the sky. I witnessed about 5 Perseid meteors during my imaging run and one can be seen at bottom left of image. Images taken with a Canon 40D and Stellarview 102ED at F/ 5.6. 12 seperate images of 5 minutes, ISO 1600 were taken in Nebulosity. Processing in Images Plus and Photoshop....Copyright Keith Grice 2010