We live in the milky way galaxy, a swirling mass of 400 billion stars, dust and at the centre a supermassive black hole. The name “milky”, (originally greek, galaxías kýklos, "milky circle”) was derived because when observed from Earth the galaxy has the appearance of a dim white band stretching across the sky. This is our place in the cosmos and it was only until the 1920’s when astronomers believed the milky way did not contain all the stars in the universe thanks in a large part to Edwin Hubble. Our galaxy is around 27,000 light years from the galactic centre to the edge which is massive but it is just one of an estimated 200 million galaxies in the universe, some smaller and some much larger. Go on a journey into the milky way in this documentary.
The milky way galaxy is not on its own in the cosmos. 50 small galaxies are confirmed to be within 420 kiloparsecs (1.4 million light-years) of our galaxy and are known as satellite galaxies together they are part of the Local Group of galaxies, which is a component of the Virgo Supercluster.
