Andromeda Galaxy is quite larger than the Milky way. The diameter of the Galaxy is 220,000 light years with the stars up to 1 trillion based on the observation. Mass of the Galaxy is 1.5 * 10^12 Solar Masses. read more
The Andromeda galaxy, the one nearest to our own Milky Way, isn't such a big shot after all. Astronomers had thought Andromeda was about two to three times the size of the Milky Way, and that our own galaxy would ultimately be overtaken by our bigger neighbor. But the latest research, published Wednesday, evens the score between the two galaxies. read more
The research also settles an old debate among astronomers about which galaxy, our Milky Way or Andromeda, is more massive. The detailed study of the dwarf galaxies allowed the researchers to weigh our own galaxy more precisely than ever before. "We are almost exactly twice as massive as Andromeda," Gilmore said. read more