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Andromeda Galaxy


Andromeda Galaxy is a spiral galaxy object of interest in space. It lies at a distance of 2.430-2.650 light years away in the constellation of Andromeda. Andromeda Galaxy was discovered in 905AD by Al-Sufi. The Spiral Galaxy's location is 00:42.7 (R.A.) and +41:16 (Dec.). Its Visual Brightness is a 3.4 Magnitude and has an apparent magnitude of 3 with an apparent dimension of 178x63 .

The Andromeda galaxy is one of the most well known galaxies (in terms of people knowing on Earth) in the universe. It is relatively close in space speak but it is not the closest galaxy to the milky way, the closest is the dwarf galaxy Canis Major Dwarf Galaxy. The Andromeda Galaxy is the closest Spiral Galaxy to our own. The Andromeda is very large and makes our galaxy look tiny. Our galaxy is 100,000 Light Years across but the Andromeda is 220,000 Light Years across. Not only is it larger in scale, it also has more stars. It is estimated that the Milky Way has about 200-400 Billion Stars but that the Andromeda Galaxy has over a trillion stars. ref:universetoday

The Andromeda Galaxy has been known of since about 900 A.D., helped by the fact that it is visible to the naked eye and still is. When it was first discovered, the discoverer would not have known exactly what he was looking at as it would`ve just appeared as a smudge in the sky. The Andromeda Galaxy will become a lot brighter in the future. However you do not need to worry as that won`t happen for billions of years. The two galaxies are moving towards one another at abotu 75 miles per second. It might seem like a fast speed but when you take into account the distance, you will understand that it will take a long time. On my galaxy page is a National Aeronautics and Space Administration (N.A.S.A.) video of galaxy collision.

When the galaxies collide, it won`t create some massive explosion like you get when two cars travelling at high speed crash into one another. There is sufficient space between the stars that some stars will pass by one another. The two galactic cores will just merge to create a new super galaxy but won`t still be anywhere near as big as IC 1101 galaxy, currently the largest galaxy known to us.

Andromeda Galaxy when it collides with us won`t be the first cosmic collision that our galaxy has had. Our galaxy has consumed other galaxies and will consume other galaxies before we reach Andromeda Galaxy. The widely accepted oldest star so far discovered, Methuselah Star is reputed to have come from another galaxy that the Milky Way consumed.

Location of the Andromeda Galaxy (M31) in the Skies

Location of Andromeda Galaxy (M31)

Fact File


NameAndromeda Galaxy
TypeSpiral Galaxy
Messier Id31
NGC Id224
ConstellationAndromeda
Right Ascension00:42.7
Declination+41:16
Distance (Lt.Yr)2.430-2.650
Visual Brightness3.4
Apparent Dimension178x63
Year of Discovery905AD
DiscovererAl-Sufi
CoprightAnglo-Australian Observatory

Andromeda Galaxy