Named for the constellation in which it appears, the Triangulum Galaxy (M33) is the third largest member of the Milky Way’s Local Group of galaxies. Only the Andromeda Galaxy and the Milky Way are bigger.
M33 lies about 2.7 million light-years away. And like its hefty galactic neighbors, it is a spiral galaxy. However, unlike Andromeda and the Milky Way, both of which are classified as barred spirals, the Triangulum Galaxy does not exhibit a central bar-shaped structure. Its spiral arms