As this is being written, early in the morning, the sun is said to be “rising”. At some deeper level, we know that the sun does not actually rise and set, but that our portion of the earth is rotating into, and out of, its light. We are no longer in the dark shadow, and will not be returning to it for nearly a dozen hours.
The moon, except for the infrequent occasions that it moves into and out of the earth’s shadow, has no dawn or dusk, no night or day. It is always blindingly bright there, with no atmosphere to interfere with the light of the sun. Pictures of the astronauts who went to the moon show that their helmets had carefully calibrated sun shades built within, the formulation and making of which had a great deal of thought behind them. One can imagine the unsung NASA engineer who determined how dark the visors had to be in order to let the astronauts see and not be blinded by the brightest light to which any human would be exposed.
The incredibly complicated programming that provides the solar system and its movements is an allegory to show how it is with us and God.
The souls in Heaven have no darkness, only day. There is nothing to screen them from The God Who made, loved, and guided them to Him. And, they do not want any such screens between them and their Maker. That’s why they’re there.
If we want to join them there, we can only begin by removing the sins that keep us from Him. Like thick clouds, sins get between us and Him. Those full of sin see only clouds, rendering He Who made them nearly invisible.