This is technologically impossible, I'm just curious if this is even possible theoretically. AFAIK light travels forever in vacuum unless they are absorbed/inhibited by something. So is it true that: At a distance of N light years from earth, we can view the light that came from earth N years ago, given that those were not inhibited by anything? So, in theory, can we view whatever has happened in the past from those light? Example: Currently, we can see galaxies billion-light years away with Hubble. The lights actually came from billion years ago. Suppose we upgrade Hubble somehow so that it is much much more sensitive to light and can focus to the inside the planet. Then suppose we instantly (yes, we have discovered instant teleportation!) put a massive amount of Hubbles spherically around earth within distance of 1 light years from earth to N light years from earth (so that it covers light from most part of earth). Then we take all the picture at the same time. Then we can view what's in the past starting from 1 years ago to N years ago given that the light is unobstructed.