Andromeda (satellite galaxy)

Andromeda is a large galaxy approximately 2.5 million light-years away from Earth and is our nearest spiral galaxy neighbor. It’s similar in shape and size to the Milky Way but contains about a trillion stars. As a satellite galaxy, Andromeda is part of a three-galaxy system in the local group, which includes the Milky Way and the Triangulum Galaxy. Over billions of years, Andromeda and the Milky Way are orbiting each other and are expected to eventually merge, forming a single, larger galaxy. Its proximity and similarities make Andromeda a key object of study for understanding galaxy formation and evolution.