The Antennae are undergoing a galactic collision. Located in the NGC 4038 group with five other galaxies, these two galaxies are known as the 'Antennae' because the two long tails of stars, gas and dust thrown out of the galaxies as a result of the collision resemble the antennae of an insect. The nuclei of the two galaxies are joining to become one giant galaxy. Most galaxies probably undergo at least one significant collision in their lifetimes. This is likely the future of our Milky Way when it collides with the Andromeda Galaxy. Two supernovae have been discovered in the galaxy: SN 2004GT and SN 2007sr.

A recent study finds that these interacting galaxies are closer to the Milky Way than previously thought—at 45 million light-years instead of 65 million light-years.