The Milky Way, along with thirty or so nearby galaxies, belongs to a collection of gravitationally bound galaxies known as the Local Group.

The Andromeda galaxy is the largest member, followed by the Milky Way and the Triangulum galaxy. The majority of the other galaxies in the Local Group are small and irregular in shape—so small that they are known as dwarf galaxies.

The Local Group is spread across a circle ten million light-years across and centered between the Milky Way and Andromeda. Cosmic background radiation studies show that the Local Group is travelling at a speed of roughly 36,000 kilometres (22,000 miles) per hour in the direction of the constellation Hydra.