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En_lizard
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why sun looks bigger in the evening? although it's closer to the Earth during noon?
Why sun looks bigger in the evening?
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In summary: This is an optical illusion caused by the difference in the distance to the sun at noon and in the evening. The sun's horizon and overhead distances are slightly greater than insignificant, with it being bigger overhead. But the difference is still small enough that the optical illusion overwhelms it.One thing I've noticed is that if you lie on the ground looking straight up at the sky, things overhead (clouds particularly) look closer than when you are standing up.This is due to the fact that you are looking at the sun from a lower angle. When you are standing up, the atmosphere is in the way and the sun appears smaller.
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tony873004
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It's not significantly closer to Earth during noon. Your eye could never percieve the difference.
I would have to guess its for the same reason as the Moon illusion. When the Moon is low, you have foreground to compare it to. That sets up an optical illusion that deceives you into thinking that it is bigger.
The Moon's horizon and overhead distances are slightly greater than insignificant, with it being bigger overhead. But the difference is still small enough that the optical illusion overwhelms it.
I would have to guess its for the same reason as the Moon illusion. When the Moon is low, you have foreground to compare it to. That sets up an optical illusion that deceives you into thinking that it is bigger.
The Moon's horizon and overhead distances are slightly greater than insignificant, with it being bigger overhead. But the difference is still small enough that the optical illusion overwhelms it.
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mathman
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One thing I've noticed is that if you lie on the ground looking straight up at the sky, things overhead (clouds particularly) look closer than when you are standing up.
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Labguy
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I believe that only happens because you (any person) are on the ground looking up from being too stoned to stand...mathman said:
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mathman
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Didn't you ever picnic in the park with your girl friend?
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Labguy
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Yes, many times but I don't recall ever looking UP.mathman said:
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turbo
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This is true. If you will Google on fovea, you will see how the non-uniformity in the eye and the non-uniformity in the visual cortex work together to give us a magnified and sharpened image in the center of our field of view. This effect is especially pronounced in birds of prey, who often have to locate their food from very high up.mathman said:
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Chronos
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In a word, refraction. The Earth's atmosphere magnifies the image.
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franznietzsche
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Labguy said:Yes, many times but I don't recall ever looking UP.
Thats just a function of positioning.
- #10
turbo
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Not enough for you to notice, and the effect is in the wrong direction, anyway. When you are looking straight up, you are looking through the least amount of atmosphere possible. The apparent largeness and sharpness of things in the center of our field of view is due to the physiology of the eye and to the manner in which the eye is wired to the visual cortex.Chronos said:
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Chronos
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Turbo is correct, it's an illusion:
http://facstaff.uww.edu/mccreadd/sectionIII.html
http://facstaff.uww.edu/mccreadd/sectionIII.html
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SpaceTiger
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En_lizard said:
If you're looking at the sun close enough to notice this, you should see an eye doctor.
FAQ: Why sun looks bigger in the evening?
1. Why does the sun look bigger in the evening?
The sun appears larger in the evening due to an optical illusion called the "moon illusion." This happens when the sun is low on the horizon and our brain compares its size to objects in the foreground, making it seem bigger.
2. Does the size of the sun actually change?
No, the size of the sun remains the same throughout the day. It is only our perception that changes due to the angle and position of the sun in relation to our surroundings.
3. Why does the moon also appear bigger in the evening?
Similar to the sun, the moon appears larger in the evening due to the moon illusion. However, the moon's distance from Earth also plays a role in its perceived size, as it is slightly closer to us during its rise in the evening.
4. Is the moon illusion the same for everyone?
No, the moon illusion may vary for different people depending on their visual perception and the surrounding landscape. It can also vary for the same person on different days, depending on the atmospheric conditions.
5. Is there a scientific explanation for the moon illusion?
Scientists have not yet reached a consensus on the exact cause of the moon illusion. Some theories suggest it is due to the refraction of light in the atmosphere, while others propose that it is a result of our brain's visual processing. Further research is needed to fully understand this phenomenon.