The accelerating expanding universe

Hi, first post on EvC forums.I was hoping that CaveDiver - or anyone else - could answer a question I have regarding the expansion of the Universe.My understanding so far is that the Universe is not expanding because all objects are explosively speeding away from each other but rather, because space itself is expanding.So my question would be, how do we know this ? How can we tell space itself is expanding ? What observations led us to this conclusion ? What is the difference between objects speeding away from us and objects being mostly stationary inside an expanding space and how can we tell the later than the former is what is happening in our universe ?Thanks in advance for your replies.Edited by break, : No reason given.

Broadly speaking yes. I am asking for some insight. I am not being confrontational or argumentative and I apologize if my post came across as such. I have tried to google for the answer but with no success. The pages I came up with describe the difference between co-moving and apparent frames and the technicalities behind an expanding space (ants on a balloon etc) but they do not explain how we know that such a thing is happening. Or in other words, what were the observations that led us to the conclusion that space itself is expanding as opposed to everything just speeding away from everything else.