When the sun was born, why did it look big but cold, and why did it look small but hot at noon?

The sun looks big in the morning because the height of the sun is still very low at this time, and the sunlight obliquely passes through the earth's atmosphere and refracts. This is the earth's atmosphere, magnifying the sun like a magnifying glass. Even at night.

At noon, the sun looks smaller, because the sun is overhead and the height of the sun is high. It can be said that the sun shoots vertically into the earth's atmosphere (at least it won't tilt too much). So there is no refraction (refraction is not obvious), so the sun is not magnified, so it looks smaller than in the morning.

The temperature is low in the morning because the sun has just come out and the earth has not been heated for a long time, just like a pot of cold water just put on a fire, which is not hot. At noon, the earth has been heated all morning, so it is very hot.

Isn't this a debate between two children?

The sun looks bigger in the morning than at noon. Is the sun closer to us in the morning and farther away from us at noon? That's not true.

Under certain conditions, people will have illusions about objects. An object looks bigger in some small objects, while an object looks smaller in some big objects.

Similarly, in the early morning sunshine, only one corner of the horizon is the sky, and the rest are backed by trees and houses. At noon, the sun has its back to the huge sky overhead, so it seems that the sun at noon is smaller than that in the morning.

In addition, the white figure we see is bigger than the black figure of the same size. This is called photodegradation in physics. When the sun rises, the surrounding sky is dark, so the sun appears bright, and at noon, the surrounding sky is bright. In contrast, the brightness difference between the sun and the background is not so big, which is why we look like the sun is bigger in the morning than at noon. In a word, the sun is the same distance from us in the morning and at noon, so its size is the same, and because of the illusion of eyes, the sun in the morning seems to be bigger than that at noon.

Also, it is hotter at noon than in the morning, is it because the sun is closer to us at noon than in the morning? Not exactly. Why is this?

It is hotter at noon than in the morning because the sun shines directly on the ground at noon and obliquely on the ground in the morning. It can be seen that when the sun is in direct sunlight, the ground and the air receive more solar radiation heat at the same time and in the same area than when the sun is oblique in the morning, so they are heated the most. So it is hotter at noon than in the morning.

In fact, the hot and cold weather mainly depends on the temperature. The main factor affecting the temperature is determined by the radiation intensity of the sun, but solar photothermal is not the main reason for directly raising the temperature. Because the direct absorption of sunlight by air is only a small part of the total solar radiation, most of it is absorbed by the ground. After the ground absorbs the solar radiation heat, it is conducted upward to the air through radiation, convection and other heat transfer methods, which is the main reason for the temperature rise.

In short, it is not because the sun is far from our ground that it is hot at noon and cold in the morning every day.

I hope you can adopt my best answer.