Artist's impression of our galaxy, the Milky Way, as it might be seen from a spacecraft approaching from above one of the galaxy's spiral arms. The Milky Way is a spiral galaxy containing about 100,000 million stars, & is about 100,000 light years across. Older, reddish stars (known as Population II stars) give the central bulge of the galaxy its warm glow, while younger, blue stars (Population I), like our own Sun, populate the spiral arms. Our solar system (not shown) is about 25,000 light years from the galactic centre, & is situated in a relatively sparse section of the galaxy.