Andromeda

The other dominant member of the Local Group, Andromeda, or M31, is a giant spiral galaxy weighing in at some 1.2 trillion Solar Masses, about 2.5 million light-years distant. It is currently racing towards the Milky Way at about 266 kilometers per second, though whether or not this will result in a direct collision is not known due to the uncertainty of its lateral motion.

Andromeda has suffered greater collisions, at least in proportion, to the Milky Way. It has little in the way of a central bar, in addition to telltale signs of a hole being punched through it due to a recent encounter. Its central black hole structure weighs in at some 140 million solar masses - nearly two orders of magnitude larger than that of the Milky Way.