The gnarled branches of an ancient tree align with a view of our Milky Way galaxy. The Milky Way is a flat, disc-like structure of stars, gas and dust measuring more than 100,000 light years across. Our Sun lies within the disc, about two-thirds of the way out from the centre, so we see the Milky Way as a bright band encircling the sky. This view is looking towards the centre of our galaxy, 26,000 light years away, where dark clouds of dust blot out the light of more distant stars. What appears to be an artificial satellite orbiting the Earth makes a faint streak of light across the centre of the image.