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Message: <blockquote data-quote="Morrus" data-source="post: 5698091" data-attributes="member: 1">Nope, it's expansion, not movement.  Space is expanding; objects in it aren't moving (well, they are, but separately to the expansion).The Big Bang doesn't have a central point; the whole universe IS the central point.  So things don't have a trajectory away from one.  Everything is moving away from everything, not just from us.And yes, space is being created between objects.  That's the whole "dark energy" thing, and we don't understand why yet.Local gravity can overcome it, as I understand it.  I'm a little fuzzy on that, but with the distances we're talking our solar system is teeny tiny and the amount of interjected space isn't enough to overpower the gravitational effects of the objects within that small area.  Even our local group of galaxies will tend to come together rather than move apart.  The amounts of space being created become massively significant when you're talking about billions of lightyears.It's a matter of scale.  Locally, gravity is pulling things together at a faster rate than space is expanding them away from us, so the net effect is that they come together.  On a universal scale, with the vast, vast distances between objects, that's not the case because the amount of space being created in between them is much, much more - so gravity is pulling them together slower than they are being expanded away, with a net effect of things spreading apart.The electromagnetic and nuclear forces are even stronger than gravity - much, much stronger.  They're held together by immensely strong forces.Magnetism, for example, is very strong.  A magnet can pull on another object harder than the entire mass of the earth's gravity can.  That's why you can pick up your keys with a magnet - that tiny magnet is much, much more powerful than the whole planet.  The forces binding atoms together are stupendously strong.</blockquote>

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