If we assume that most of the mass of a galaxy is made up of stars, we would assume that most of the galaxy’s mass is distributed toward the center of the galaxy, in the parts of the galaxy where thos...If we assume that most of the mass of a galaxy is made up of stars, we would assume that most of the galaxy’s mass is distributed toward the center of the galaxy, in the parts of the galaxy where those stars are more numerous. Observations of the rotation speed of gas in the outer regions of the Milky Way Galaxy indicate that the gas is orbiting the center of the Galaxy with a velocity of 220 km/s.
