Considering that the universe is either infinite or at least Douglas Adams style big, surely the likelyhood of there being a star in every possible direction is high. Light in a vacuum for millions or billions of years is still light.
In: Physics
We do received light approaching from everywhere all the time, but thanks to the inverse square law and the speed of light, it can take billions of years for light to reach us + the density of photons decreases considerably the further you move away from the point of emission.
That means that light emitted from our sun takes minutes to reach us and illuminates our sky, yet it would take 4 years to reach Alpha centauri, our closest neighbour, and would hardly be visible in the nightsky.
Similarily, light from stars further away are not bright enough to trigger a response from our retinas. That’s why telescopes can see stars that we can’t simply because their sensors are way more sensitive.
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