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sun through clouds

So I have a layman question. If we look at the angle of the sun rays, doesn't sun seem much closer than it is [150 million kilometers]

cant we take those angles that the sun makes with the earth, take approximate distance from those points and use angle-side-angle to calculate the distance from sun to earth?enter image description here

how can we even get these angles if the sun is so far away

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Here is an image of rays from two sources from side.

enter image description here

Compare that to an image of rays from the same two sources from base.

enter image description here

The particular perspective gives no information about the distance of the two sources.

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  • $\begingroup$ but are we looking at the rays from the base or from the side on the picture of the sunrays? $\endgroup$
    – Nasal
    Commented Sep 20, 2019 at 11:17
  • $\begingroup$ How many degrees would you expect the rays to diverge from the side of a 150 million km long cone? How many degrees do they diverge in the picture? $\endgroup$
    – Dale
    Commented Sep 20, 2019 at 11:27
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When you take a photo, straight lines remain straight. Sun rays are straight, so they remain straight. Since all sun rays have their origin at the sun, they must be pointing away from the sun radially. Both in 3D and in the image you take.

Now, take your image, and extend the visible sun rays back towards their origin. You will notice that those extensions converge exactly where the sun happens to be in the image (if it's within the image).

The illusion stems from two origins:

  • The sun is within or near to the visible image frame, but not visible itself because it is hidden by the clouds.

  • Your eyes correctly locate the 2D position of the sun within the image, but attribute a too small z-coordinate to it (distance from the observer). This z-coordinate cannot be determined from a single 2D image, and is thus just a guess by your visual cortex.

    This guess assumes that the directions of the sun rays have no strong z-coordinate, but in reality, they are almost z-coordinate only.

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