Why are the days longer in summer than in winter?

Why are the days longer in summer than in winter?

Why are the days longer in the summer than in the winter? Because the Earth's axis is slightly tilted, which is the main factor determining the length of the day.

In the solar system, the Earth revolves around the Sun like other planets. In addition, the Earth also rotates around itself - it rotates.

Earth's Axis

Let's explain it this way. Suppose the Earth rotates around an imaginary axis that connects the North Pole and the South Pole of the Earth. We call it the Earth's axis.

So how does the Earth's rotation and axis affect the length of the summer day? The tilted axis causes the Earth to receive different amounts of sunlight throughout the year.

Summer Solstice

When the Earth's axis (northern or southern) begins to tilt towards the sun, it is called the summer solstice.

Northern Hemisphere Summer Solstice

The summer solstice in the Northern Hemisphere is also called the June solstice. It occurs around June 21. Most of the time, the summer solstice in the Northern Hemisphere is June 20 or 21. June 22 is relatively rare. The next June 22 solstice will occur in 2203.

Southern Hemisphere Summer Solstice

The summer solstice in the Southern Hemisphere is on December 21 or 22 every year. Therefore, the summer solstice in the Southern Hemisphere is also called the December solstice.

So why are the days longer in the summer?

Earth's position in summer

To explain this phenomenon, we can divide the earth into two hemispheres - the northern hemisphere and the southern hemisphere - along an imaginary line - the equator. In the summer of one hemisphere, the earth is tilted towards the sun.

The Earth is tilted towards the Sun at an angle of 23° 26', the maximum angle the Earth can tilt. As a result, the Sun is highest in the sky as seen from that hemisphere during this season.

For example, in the Northern Hemisphere, the sun reaches its northernmost position at this time. Therefore, the days get longer in the summer; on June 21, the day in the Northern Hemisphere is the longest of the year. But remember, although it appears from Earth that the sun is moving around the Earth, it is actually the Earth that is moving around the sun.

The situation in winter is just the opposite of that in summer. In winter, the semi-axis is away from the sun.

Therefore, the northern hemisphere receives very little sunlight in winter, so the days are also very short in winter. However, when it is winter in the northern hemisphere, it is summer in the southern hemisphere because the southern axis is tilted towards the sun at this time. This is why the summer in the southern hemisphere is in December.

Earth's revolution

Equinoxes (Spring and Autumnal Equinoxes)

The equinox is the time of year when the day and night are equal in length. There are two equinoxes each year, one on March 21 or 22 (the spring equinox) and the other on September 22 or 23 (the autumnal equinox).

Sometimes, however, the spring equinox occurs on March 19. At the equinox, the Earth's axis is perpendicular to the direction of the sun.

At this time, the northern and southern hemispheres receive the same amount of sunlight.

The Earth's relative position in the solar system and its rotation determine the four seasons, the summer and winter solstices, and the spring and autumn equinoxes. With this knowledge, you will understand why the days in summer are longer than those in winter.

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