There are galaxies of different sizes and type. Typical galaxies range from dwarfs with as few as ten million (10) stars up to giants with a hundred trillion (10) stars, all orbiting the galaxy's center of mass. Galaxies may contain many multiple star systems, star clusters, and various interstellar clouds. The Sun is one of the stars in the Milky Way galaxy; the Solar System includes the Earth and all the other objects that orbit the Sun.