What Is The Reason For Different Seasons?
Man has been curious about the change of seasons, since the earliest times. Why the summers are warm and winters are cold. Gradually the days grow longer in spring, and in the winters, the nights are so long.
The earth revolves around the Sun and simultaneously the earth revolves on its own axis. It is spinning like a top as it moves around the Sun. We take the line joining the North pole and the South pole as the axis of the earth. If the axis of the earth were at right angles to the path of the earth around the Sun, there would have been no different seasons. The days and nights would have also been of the same duration.
The axis of the earth is tilted. There are certain forces at work on the earth and this is the reason for this tilt. The pull of the Sun, the pull of the moon, the spinning action of the earth itself. This all results in a tilting motion of the earth around the Sun. This position is maintained year-round and the earth’s axis always points in the same direction, towards the North- star.
It amounts to, that during part of the year. the North pole tilts towards the sun and part of the year away from it. Due to this tilt, the direct rays of the sun sometimes fall on the earth north of the Equator, sometimes directly on the equator, and sometimes south of the equator. This difference in the way of the strike of rays on the earth causes the different seasons in different parts of the world.
The countries north of the equator have a summer season when the Northern Hemisphere is turned toward the Sun. During this period of time, the winter season is enjoyed in the countries south of the equator. When the Sun shines directly on the Southern Hemisphere, the people in that part of the world have summer season, and the countries North of the equator have winters. The longest and shortest days of each year are called “the summer solstice” and “winter solstice”.
Only on two days in the year the day and night are equal all over the world. In the spring they come and fall just halfway between the solstices. One is the autumnal equinox, which occurs about September 23, and in the spring it occurs about March 21.