Transcription: It takes the Earth a year, 365 days, to orbit the Sun. As it does so, it spins about its own axis once every 24 hours, giving us our familiar cycle of day and night. The axis of the Earth is tilted at a constant angle to the Sun and it's because of this tilt that the northern and southern hemispheres experience their changing seasons. During the time of year we know as winter in the northern hemisphere, the North Pole is tilted away from the Sun. The Sun's rays have to pass through a lot of atmosphere to reach the surface of the planet in the northern hemisphere and so little heat reaches the ...
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