# Crepuscular and Anticrepuscular rays

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You may have seen images like the one below showing Crepuscular and Anticrepuscular rays, or you might have seen it yourself.

Sometimes people say that this phenomenon indicates that the sun is local and not very far away. What is usually claimed is that the beams of light would converge to a point not too far above the earth. Let us examine this here.

The below photos were taken by me a few years ago. If we follow the above logic the sun should be just behind the trees.

The photo below was taken on the same occasion, but from the side, perpendicular to the direction of the other photo. We can see that the sunbeams are parallel, not converging to a point behind the tree.

It is quite similar to that parallel train tracks seem to converge at a point, even though they would actually not meet. This is a question of perspective.

Hopefully, you know that the tracks do not intersect a bit in front of the mountains.

The photos below are yet another way to illustrate the point. The sticks are close to parallel,

When the same sticks are seen from above they seem to converge at a point not too far down in the ground. But I hope you don’t think they do.

So the thing is that if the beams of light are close to parallel, and directed toward you, then they would look like they do converge.

But say the sun is actually local and the beams are not directed toward you, but to the ground or sea as it looks like?

The clouds are definitely not that many miles or kilometres away, and we can see some openings for the light to shine through, in particular on the left side.  We know that clouds are not that high up in the sky, as anyone who has flown on a commercial jet flight knows.  I have, on purpose, chosen beams that look like they reach the ground at 45 degrees. That means that the beams would converge at twice the height of the clouds, or at most a few miles or kilometres away. Say you see the sun to the east.  Call a friend living a few tens of miles or kilometres directly to the north or south of you.  Ask them in what direction they see the sun. If the sun is this local then they will see the sun in some other direction than directly to the east, but you will find that they will see the sun in the same direction as you. Go figure.

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