Replies

The chances that any of the planets in our solar system start 'wobbling' is close to zero, unless a large singularity wanders through our neighborhood, in which case all bets are off. I'd be more worried about something like a GRB pointing our way. Chances of that are also minute, although it would only take one...

A "universe that collapses back" was the prevailing point of view at one point, and the idea does have a certain symmetry, but evidence now points to a universe that is not only continuing to fan out (into what is another question), and is in fact accelerating as time goes on. I don't adhere to the theories about 'dark' matter and 'dark' energy ad nauseaum; there has to be another explanation. But the phenomenon is both real and measurable.

One of the most intriguing aspects of this expansion is that it's velocity is not bound by the speed of light, since it is space itself that is expanding. Einstein's theories of spacetime are incomplete; as far as I know they do not address this particular phenomenon at all.

Ultimately, there's little we can do about it; we are simply along for the ride. And like everything else in the natural world, it doesn't require our understanding to function just fine.