Crepuscular rays. It's a perspective effect.
And well documented at that. If you actually measure the rays, they are parallel.
More word trickery.
When you say "THEY" are parallel, this is misleading. Even the evil Wikipedia states that "the rays are in fact near-parallel shafts of sunlight." Notice the word "NEAR." Near is not the same as EXACT. In other words, because they are not perfectly parallel, they do indeed have an angle.
In truth, the concept is based on deception. There is partial truth in the statement; but the rest which they
don't explain is what allows for the lie.
The sunbeams that are close to one another are
almost parallel - yet at the same time a slight angel exists, as wiki states (though vaguely). But the farther the beams are from one another, the more the slight angles compound to add up to a large angle.
Wiki makes the same deliberate error the butt-hole above makes in comparing this to railroad tracks which are moving away from the observer. The sunbeams however are not moving away, but are viewed from a distance, straight on, to the side view—Thus the angle observed is true.
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