When will the collision between the Milky Way and Andromeda happen?
Q: When will the collision between the Milky Way and Andromeda happen?
A: The collision will happen about four billion years in the future.
Q: How fast is Andromeda approaching the Milky Way?
A: Andromeda is approaching the Milky Way at about 110 kilometres per second (68 mi/s) as shown by its blueshift.
Q: Was it known before 2012 whether or not the collision between the Milky Way and Andromeda was going to happen?
A: Until 2012, it was not known whether the possible collision was definitely going to happen or not, because its proper motion was too small to measure.
Q: How did researchers conclude that the collision between the Milky Way and Andromeda is sure to happen?
A: Researchers concluded that the collision is sure to happen in 2012. They used the Hubble Space Telescope to track the motion of stars in Andromeda between 2002 and 2010 with great accuracy.
Q: Has Andromeda collided with another galaxy in the past?
A: Yes, Andromeda has collided with at least one other galaxy in the past.
Q: What is expected to happen when Andromeda collides with the Milky Way?
A: It is expected that Andromeda will collide with the Milky Way in around 4 billion years.
Q: Are collisions between galaxies common?
A: Yes, such collisions are relatively common.
