Crepuscular rays are an example of perspective. Parallel lines converge to a distant point . With the Sun at 93 million miles away the light rays that reach us are very close to parallel. Discovery of the laws of perspective truly changed art to be more realistic long before photography was invented.
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Yes, parallel lines, very good. Crepuscular rays can always be traced back to the location of the Sun in the sky and have nothing to do with the distance to the Sun. It is an illusion because sunlight is reflected off of dust particles in the air and redirected back to our line-of-sight.
Perspective is linear, an object twice as far away is half the angular size.
Size of Sun: 860,000 miles, 0.86 million miles.
Distance from Earth to Sun: 93 million miles.
Angular extent: 0.86/93⋅(57.3°/ Radian) = 0.53°
The apparent size of the Sun in the sky is ~0.53°
The Moon is 400 times smaller than the Sun but is also 400 times closer to the Earth. Since angular extent is linear, the two cancel out and the Moon appears the same size as the Sun, by design.
Size of Moon: 2,158 miles,
Distance to Moon: 239,000 miles.
Angular extent: 2,158/239,000⋅(57.3⋅/Rad) = 0.52°
“The Moon is 400 times smaller than the Sun but is also 400 times closer to the Earth.”
Pure coincidence.
Lol.
One of the neat calculations you can do with the Moon is how fast you’d have to travel on its equator to see the Sun sit still, that is the velocity of its spin at its equator. The answer is 10.3 miles per hour which is easy enough to do with a fast walk!