Messier 31: Difference between revisions

==Future collision with the Milky Way==

The Andromeda Galaxy is approaching the Milky Way at about 110 kilometres per second (68 mi/s). It has been measured approaching relative to our Sun at around 300 kilometres per second (190 mi/s) as the Sun orbits around the center of our galaxy at a speed of approximately 225 kilometres per second (140 mi/s). This makes Andromeda one of the few blueshifted galaxies that we observe. Andromeda's tangential or side-ways velocity with respect to the Milky Way is relatively much smaller than the approaching velocity and therefore it is expected to directly collide with the Milky Way in about 4 billion years. A likely outcome of the collision is that the galaxies will merge to form a giant elliptical galaxy or perhaps even a large disk galaxy. Such events are frequent among the galaxies in galaxy groups. The fate of the Earth and the Solar System in the event of a collision is currently unknown. Before the galaxies merge, there is a small chance that the Solar System could be ejected from the Milky Way or join M31.

==References==