For example one rocket stays in Earth orebit and the other fires a roct and speeds away but what if the case is that the two rockets are already in motion and by firing a rocket is actually slowing in relation to a larger reference point? e.g. the rockets are moving at 60,000km/s when local...
I am not a physics major but have always been perplexed by the apparent paradox of two issues:
1. If we use the Hubble telescope to view items 10B+ years in the past yet the universe is expanding, what was the actual physical location of these bodies at the time the light was produced...