The seasons are caused by the tilt of the Earth's axis, which is about 23.5 degrees. This means that as the Earth orbits the sun, different parts of the planet receive more or less sunlight at different times of the year. The more sunlight a region gets, the warmer it is. The less sunlight, the colder it is.
The Earth completes one orbit around the sun in about 365 days, which we call a year. During this time, the Earth's axis always points in the same direction, towards a star called Polaris. This means that as the Earth moves around the sun, the northern and southern hemispheres experience opposite seasons.
For example, when the Earth is on one side of the sun, the northern hemisphere is tilted towards the sun and gets more sunlight. This is summer in the north and winter in the south. When the Earth is on the other side of the sun, the opposite happens. The northern hemisphere is tilted away from the sun and gets less sunlight. This is winter in the north and summer in the south.
The seasons change four times a year, when the Earth reaches certain points in its orbit. These are called equinoxes and solstices. An equinox is when day and night are equal in length, because the sun is directly above the equator. A solstice is when one hemisphere has its longest day and shortest night, or vice versa, because the sun reaches its highest or lowest point in the sky.
The spring equinox occurs around March 20th or 21st in the northern hemisphere and September 22nd or 23rd in the southern hemisphere. The autumn equinox occurs around September 22nd or 23rd in the northern hemisphere and March 20th or 21st in the southern hemisphere. The summer solstice occurs around June 21st or 22nd in the northern hemisphere and December 21st or 22nd in the southern hemisphere. The winter solstice occurs around December 21st or 22nd in the northern hemisphere and June 21st or 22nd in the southern hemisphere.
Remember to enjoy each season for its unique beauty and charm!
Unless stated otherwise, all images are created with Bing's AI by me.