How can galaxies collide if they are moving away from each other?

Answer 1

Not all galaxies are moving away from each other. In fact the galaxy Andromeda is moving toward the Milky Way and they will eventually collide, because Andromeda is so much bigger than our Milky Way it will preatty much eat us and ruin our galaxy. Good news: it won't happen in our life time, and we are the 2nd largest gallaxy in the Local Group and no other (known) gallaxies are moving toward us.

Answer 2

Yes our galaxy moves. It spins through space around its center which contains a massive black hole, it moves in relation to our local group of galaxies, and it moves relative to the distant galaxies as well. If you stop and think about it, there is absolutely nothing anywhere that can be said to be motionless.

Answer 3

Most galaxies are moving away from one another, and this is, according to the theory, a direct result of the ongoing expansion of the universe from the time of the initial expansion, the so-called big bang. The reason some galaxies are moving toward one another (and routinely colliding, actually) is because some galaxies are moving in groups or clusters. They have come close enough together that their mutual gravity keeps them together, orbiting around one another or moving in other ways. The Andromeda Galaxy, one of the closer star groups to the Milky Way, is on a collision course with the Milky Way. If you are around in about 5 billion years, you may get to see the night sky change completely as the chaos of the collision re-arranges all the stars in both galaxies.

Answer 4

Galaxies are mostly moving away from each other, due to the continual expansion of the universe from the Big Bang. Not all galaxies are; for example, the Andromeda Galaxy is approaching our Milky Way, and they will probably collide and merge in about 4 billion years.

The further away a galaxy is, the faster it seems to be moving away from us. This is one part of the data on which Edwin Hubble's idea of an expanding universe was based.

Answer 5

Galaxies in the universe are not all moving away from each other. In some cases, two galaxies that are relatively close to each other can be gravitationally bound and eventually collide due to the interaction of their gravitational forces. This is more likely to happen in clusters of galaxies where gravitational interactions can overcome the expansion of the universe between them.

Answer 6

because the universe is expanding from the big bang.

Answer 7

Yes, in my universe all of the galaxies are moving relative to each other.