A Swarm of Dwarf Galaxies Buzz Around Our Milky WayThe Milky Way is the galaxy that contains our Solar System and is part of the Local Group of galaxies. It is a barred spiral galaxy that contains an estimated 100–400 billion stars and has a diameter between 150,000 and 200,000 light-years. The name “Milky Way” comes from the appearance of the galaxy from Earth as a faint band of light that stretches across the night sky, resembling spilled milk. tabindex=0 Milky Way’s Twin.