It has been known for last few centuries that our planet earth has two different forms of motion. It rotates on its own axis and also revolves around the sun. The spinning of Earth on an imaginary line passing through the north and south pole is known as its rotation. On the other hand, Earth's travel around Sun in an elliptical orbit is called revolution. Earth's rotation on its own axis takes about 24 hours and that is the duration of our day. Earth takes about 365 days to complete one revolution around the sun and this is the duration of our year. Earth's rotation results in the phenomena of day and night. In comparison, Earth's revolution causes seasons (autumn, fall, spring, etc.). It is the rotation of earth that results in different times in different countries (one that is facing sun has day hours, while the opposite region has night hours, etc.).
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