Why don’t we constantly see new stars in the sky as an increase of light travels to us?

Question

with how light works and the constant expansion of what we term the “observable universe” why don’t we constantly see new stars appearing in the night sky as the observable part expands and stars/galaxies light reaches us for the first time?

The night sky has stayed relatively the same (accounting for changing postions over time, stella phenom, supernovas etc.) for all of humans written history.

In: 515

Answer 1

I think the best way to visualise the expansion is to think of a ballon full of dots on its surface, each dot representing a galaxy. And when you blow the ballon up those dots moves further and further apart.Now we will notice that the speed of the expansion between two neigboring dots is X, but if we look at dots that are 2 places apart, they move apart at 2X speed. Same applies for galaxis in that the further away something is from us, the faster it is also moving away from us because theres more space between us that is continually expanding itself.

Now imagine our observable universe is a set distance on this balloon thats as far as we can currently see before expansion exceeds the speed of light. Think of a circle that isnt stuck to the ballon but just a physical circle we lay on the baloons surface. As we blow it up more and more dots will move from inside this circle circumference to outside of it. Same goes for galaxies, as time goes on less and less galaxies will be observable.

​

In 10-30 billion years a civilization of similar tech as we do would probably only be able to detect its local galaxy cluster and come to very different conclusions about the universe then we have. Fast forward further and a civilization would proclaim their glaaxy to be all there is.

​

Now im not sure i understood completely but it sems this expansion isnt constant but are growing. So one hypothesis is that this expansion will eventually win out gravity and even the molecular forces in the end. Scatter the galaxies, solarsystems, planets and at last break apart the individual atoms… Sounds insane but who knows… ive not looked into the math behind it.