The seasons are caused by the Earth’s orbit around the sun and the tilt of the Earth’s axis. The Earth orbits, or travels around, the sun in a path that is shaped like an oval. It takes about 365.24 days for the Earth to make one complete orbit around the sun.

As the Earth orbits the sun, different parts of the Earth are exposed to different amounts of sunlight. When the Earth is tilted towards the sun, the sun’s light shines directly on the Earth and it is warm. This is called summer. When the Earth is tilted away from the sun, the sun’s light is not as direct and it is cooler. This is called winter.

The Earth’s axis is an imaginary line that runs through the North Pole and South Pole. The Earth’s axis is tilted at an angle of about 23.5 degrees. This tilt is what causes the seasons.

When it is summer in the the Northern Hemisphere the Northern half of the Earth is tilted towards the sun and it gets more direct sunlight. The Southern Hemisphere is tilted away from the sun and it gets less direct sunlight. During the winter, the opposite is true. The Northern Hemisphere is tilted away from the sun and it gets less direct sunlight. The Southern Hemisphere is tilted towards the sun and it gets more direct sunlight. Thus, when it is winter in the Northern Hemisphere it is summer in the Southern Hemisphere.

Understanding the causes of the seasons can help us learn more about the Earth and how it moves in space. It can also help us understand why the weather is different during different times of the year.