Where it can be seen from
In the plains of the African night, where there is no light pollution given from cities, they are immersed in the light of a billion suns and the Andromeda galaxy. The sky is taken over by the large vibrant arc of the Milky Way galaxy, a silver mist of stars in huge numbers that are impossible to count. Every single point of light and every patch of magnificent mist visible to the unaided human eye have as their origin a star in our own galaxy, or the misty clouds known as the Magellanic clouds – two small dwarf galaxies in orbit around the Milky Way. All except for one…
How to find Andromeda
For it to be found, you first need to recognise the distinctive ‘W’ shape of the constellation of Cassiopeia. This sits on the opposite side of polaris, the North Star, to the constellation Ursa Major, otherwise known as The Great Bear or The Plough. As Cassiopeia is so close to Polaris, it is a constant feature in the northern skies – every 24 hours it rotates around the pole and never drops below the horizon at high latitudes. If in your mind’s eye you put the ‘W’ of Cassiopeia upright, the just beneath the rightmost ‘V’ you will be able to see quite a large, faint, misty patch in the sky. In comparison to the other stars around it, it is of similar brightness, but a lot dimmer than the stars of Cassiopeia. This is seen to be extremely stunning object that can be seen alone by the naked eye and it is its own entire galaxy beyond the Milky Way. It is named Andromeda, and is our closest galactic neighbour. A trillion suns can be found in this galaxy, thats twice the amount of stars that can be found in our galaxy. It is around 25 million million million kilometres away.
View of Andromeda and surrounding galaxies (Andromeda seen on the left hand side)
Time it took to reach us
Two and a half million years ago, when our distant relative Homo habilis was searching for food over the Tanzanian savannah , a beam of light left the Andromeda Galaxy and begun its journey across space at the speed of light, generations of pre-humans and humans lived and died. Species and species in this time came and went, until two and a half million years on, this light reached our planet.