>It isn't necessarily the case that nothing leaving Earth today could ever get past that horizon. Light can travel forever if nothing ever scatters it. Given so

>It isn't necessarily the case that nothing leaving Earth today could ever get past that horizon. Light can travel forever if nothing ever scatters it. Given some very large amount of time, it can beyond the boundary depicted there. Careful with that. You could indeed aim a beam of light to deep space trying to reach something on the edge of the observable universe, and that beam could indeed some day travel 46.6 billion light years[1] away from the Earth, however the beam could never reach the stars[2] that were right on the edge when you shot out the beam, because those stars[3] would have receded out into the event horizon in the intervening time. [1] The current radius of the observable universe is greater than the age of the universe due to expansion. [2] Or whatever happened to be at that same location after countless billions of years. [3] Actually it's not the stars receding, but the space those stars reside in.