This Hubble Space Telescope image shows a small section of M31, the Andromeda Galaxy. It is our closest large galactic neighbor, at a distance of about 2.5 million light-years. The galaxy’s busy core, which is packed with stars, is at lower left. Lanes of dark dust and bright blue stars outline the galaxy’s spiral arms, where new stars are born. This view spans about 60,000 light-years and shows roughly 100 million individual stars. [NASA/ESA/J. Dalcanton, B.F. Williams and L.C. Johnson (University of Washington)/PHAT team/R. Gendler]
Find out more in our radio program entitled Andromeda Galaxy.