For a long time people tried to understand and explain various natural phenomena – why it is raining why day is replaced at night why there is a change of seasons. But also now some people think that change of seasons is caused by remoteness of Earth from the Sun. Actually it not so.
Instruction
1. As you, probably, know, Earth is in the constant movement. Its rotation causes change of day and night round its pivot-center, the speed of rotation determines length of terrestrial day. One turnover of Earth of an orbit around the Sun is one terrestrial year.
2. A terrestrial axis – the imagined line connecting the North and South Pole. It has a certain tilt angle to the orbit plane (ecliptic plane) of the planet. An axis tilt angle - the constant also makes 23.5 degrees. The terrestrial axis is permanently sent to one point – on the Pole star. Existence of a tilt angle of an axis of the planet to the plane of its orbit also caused a change of seasons.
3. Thanks to existence of a tilt angle of a terrestrial axis to the ecliptic plane, the same parts of the earth's surface at different times its movements on an orbit are lit with the sun differently, that is receive different amount of heat and light.
4. A part of year the earth is turned to the Sun by the North Pole, other part of year – Southern. That is, a part of year the Northern hemisphere receives bigger amount of heat and light heats up stronger. In the territory of located north of the equator spring and summer succeed winter cold weather. The southern hemisphere is hidden from direct sunshine at this time. The sunshine "sliding" on the Earth's surface bear not enough heat and south of the equator there comes the fall and winter.
5. As the tilt angle of a terrestrial axis does not change, at the further movement of the planet on an orbit (that is other part of year) inclined to the Sun is the South Pole. The southern hemisphere receives more heat and light, south of the equator the spring comes. The northern hemisphere, receiving less sunlight, gradually cools down. North of the equator – winter.
6. The equatorial zone of Earth constantly is under direct sunshine therefore on the equator of a change of seasons does not happen.