Do you have at least some idea why it's warm in summer and cold in winter?
It's because the position of the earth's axis with respect to the sun changes as the earth revolves around the sun.
As you can see from the above diagram the axis of earth and the rotation of earth also sunlight is shown. There is morning in the area where is sun and night time on the other half.
complete trip around the Sun, seems simple enough but there is a problem the earth doesn't travel on a path around the Sun that returns to its starting point so how do we know when a year starts or ends well one way called a Siberia year measures our orbit against the distant stars as viewed from the earth our orbit causes the Sun to appear to move through the constellations of point a sight Tyrael year has passed this motion is difficult to observe directly because the Stars cannot be seen when the Sun is in the sky however if you look at the sky before its dawn the annual motion is very noticeable.
The last stars seem to rise are not always the same and within a week or two an upward shift can be noted as an example in July in the northern hemisphere Orion cannot be seen in the dawn sky but in August it becomes easily visible measuring a year this way gives a period that is 365 days 6 hours 9 minutes and 10 seconds long another possibility is to measure the year against the passing of the seasons because of the tilt of the Earth on its axis the position of the Sun in the sky changes from day to day throughout the year if we were to take a picture of the Sun at noon regularly throughout the year we would see the Sun moving on this path called an analemma on the days in its orbit when the earth is at a maximum tilt towards or away from the Sun the length of the daylight is at a maximum or a minimum these days.
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