What is meant by galaxies that are "interacting?"

Question

Clara Avalos · Accepted Answer

When galaxies are said to be 'interacting' this usually means they are either colliding, beginning to collide or have collided.

The Andromeda Galaxy, which is our nearest galaxy to the Milky Way, will collide with the Milky Way in a few million years, increasing the mass of our galaxy and causing the skies to glow with billions of stars as it approaches. I believe this will happen. This time, there will be an additional intriguing aspect that is technically nonexistent: the moon will have been launched into space, much like Mars's moons, and will either be captured by another planet or our sun, collide with another object, or start a cosmic journey. So, even in the unlikely event that Earth is destroyed before the Andromeda Galaxy collides, there may still be a portion of Earth remaining. I hope the extra information and this help.

Luke Allen · Answer

undefined Galaxies that are "interacting" are those that are gravitationally close enough to each other to affect each other's trajectories, structures, and shapes; over time, this interaction can lead to tidal tails, distortions, and even mergers between galaxies.