Why are galaxies flat??

Question

Why are galaxies flat??

Answer 1

Because they are spinning they are kind of being thrown out but still held together.

Answer 2

its rather a simple vector problem, just hard to describe.  Every particle (sun or dust) is being acted on gravitationally by every other particle in the system... BUT.... many of them cancel out... its like if there are as many in one direction as the other, then disregard both.

anyway... it comes down to, picture a particle just above the rotating plane of the galaxy... there are many more particles acting on it (pulling on it) from below, than above, so which way will it go?  Many particles will find their way to the plane of rotation this way.  Of course, that means that others will too as there becomes fewer forces holding them away to balance.

Answer 3

Just the way God made them

Answer 4

They're not all flat. Elliptical galaxies can be nearly spherical.

Answer 5

Ok here's a simple explanation. Right...

Firstly not ALL galaxies are flat. Only spiral and disk galaxies are flat. There are many eliptical ones that are almost perfect circles.

Secondly, the ones that are round are usually acted on by gravitational forces, dark matter, and of course, centrifugal forces. And besides they are not "flat" they are actually a couple of hundred to thousand light years wide. In perspective the closest star to us is 4.6 light years away... But remember they can be up to 250,000 light years wide plus. Think of it this way. They are flat because they spin and are flattened out by all the huge forces surrounding them. Hope this helped.

Answer 6

cause we dont have 3D images of the galaxy so we can make a small clip to show people that they arnt    

NO GALAXY IS FLAT!!! JUST NOT POSSABLE