how can galaxies collide in the expanding universe?

Question

the big bang theory says that everything in the universe is moving away from each other which would seem to preclude any collisions, nes pas?

Answer 1

Local groups. especially a special class of compact group called a "Hickson group," can be so tightly gravitationally bound that galaxies in those groups attract each other. Our own galaxy will collide with the Andromeda galaxy in the future. We are already moving toward each other and accelerating. In a couple of billion years, you will get to see such a collision up close and personal.

Answer 2

The statement that the Universe is expanding is an approximation that holds on the largest scales. On the very largest scales, bigger than 100 Megaparsecs, it is an excellent approximation.

Futhermore, it means that "space" is actually expanding, the spacetime manifold, and everything in it, is expanding. On small scales, however, the spacetime manifold can be stable or contracting.

Regions the size of a cluster of galaxies and smaller are not expanding---they are contracting. If the local density exceeds a critical density, then that region will contract. The Earth, the Solar System, the local group of galaxies, and the Virgo supercluster are not expanding---they are contracting or more-or-less stable.

Answer 3

have you ever heard about the point at the edge of the universe, it's not really the edge, it's only the edge of the visible universe(which is approximately 15 billion light years away) which has me contemplating the big bang theory, i don't know what to believe instead of this but when exactly did the big bang theory come into being,

can our universe be that massive that the big bang was a multiple of big bangs in an ever expanding universe.

someone told me that our sun is like a nucleus of an atom and the earth and the planets around it are examples of protons and neutrons which create biological cells, e.g you me and the people around us
i don't think this is the answer you want but it might help in some way

Answer 4

Locally, gravitational influence will play a part.

Just because the Milky Way and M31 are approaching each other, does not discount that the local group of galaxies, which includes us and M31, is moving out as a mass, as part of the universal expansion.

You might as well ask why the planets continue to orbit the sun, or even why you are stuck to the Earth. Gravity.

Answer 5

the growth is an frequently used tendency that's bigger because of the fact the gap between galaxies gets bigger. for extremely close galaxies, the cost of growth interior reason small and is overwhelmed by potential of the gravity of the galaxies themselves. The Andromeda galaxy is fairly interior attain galactic standards, so the gravity betwen our Milky way and it relatively makes them advance nearer jointly. a matching attention applies for the galaxies themselves. to quite see the growth consequences, you need to have distances on the order of tens to 1000's of thousands and thousands of light years. Galaxies are 'in basic terms' some hundred thousand lightyears for the time of. because of this, the gravity contained in the galaxies is greater advantageous than the growth.

Answer 6

Yes, but some objects are moving faster than others, and you're forgetting the universal equalizer: gravity.

Galaxies and all their contents have mass and therefore gravity, just like everything else. So as one galaxy passes another, they tug on one another. These tugs can often send stars, planets, and other objects hurling through space; they can also alter a galaxy's course so that it collides with its neighbor.

Answer 7

In addition to the general expansion, there is local motions.
For eg Andromeda galaxy is nearing towards milky way.
Even though the big bang is happening,planets don't get way from solar system as local gravity take care of it.In the same way, local motion are different than the general expansion by big bang

Answer 8

Ants can run around on the surface of an inflating balloon and collide couldn't they? So too can galaxies run around and collide even though the universe containing them is expanding.

So: Voila, oui il est possible!

Answer 9

it's something to do with clusters, galaxies are all in clusters, and all the clusters of galaxies are getting further away from each other, but the galaxies in the same cluster are all kinda connected by gravity and they might collide. the wilky way galaxy is maybe going to collide with the andromeda one, in like 3 zillion years time

Answer 10

well just because there is more space in the universe doesn't mean it is all being used. galaxies move where it "wants" to move.
like if you are in a room {that is 100x100 sq. ft.} with 10 other people you don't have to stay in your respective area, chances are you are going to be near another person (because you wnat to )