The Hubble Space Telescope offers a new view of the powerful merger of two spiral galaxies: a preview of what may happen when the Milky Way collides with the neighbouring Andromeda galaxy in several billion years. The Antennae galaxies shown here started to interact a few hundred million years ago, producing long tails of material left behind by tidal disruption and inspiring their naming. While the stars themselves are unlikely to collide during the merger, the violent collision of the gas and dust clouds triggers intense star formation. The brilliant points in the image are star-forming regions surrounded by glowing hydrogen gas appearing pink. Most of the young stellar clusters – visible as faint blue dots – will disperse in the next million years, but it is believed that about 100 of the most massive clusters will survive to form regular globular clusters, like those in the Milky Way (CERN Courier July/August 2006 p10). Image: NASA, ESA and the Hubble Heritage Team [STScI/AURA]-ESA/Hubble Collaboration.