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1

This is not quite an answer but more than a simple comment. When I speak about distances I mean (angular) distances in the sky, when i speak about position I mean position in the sky. I adhere to terrestrial observer's point of view. 1, Starry sky (and everything on it, including Sun, Moon, planets) rotates around a point near Polaris (north celestial pole) ...


4

Though I see the answer a few times, I feel that they are too complicated for a student. I'm 13 and my dad pointed me to this thread. Here's how I see it. The Earth spins, and the Earth revolves around the Sun. The amount of time that it takes for a star to spin all the way around and appear again at the same spot is different than the amount of time that ...


15

All of the other answers are fairly technical, but a decently simple logic chain forces time zones to be 360° / 24. Consider this: Since there are 24 hours in a day, it makes sense to divide the Earth into 24 time zones. There are 360° in a circle, because that's how degrees are defined. To completely cover the circumference of the Earth, you must account ...


0

If you say that one place is one hour ahead of another, that means that the time of day at which the sun reaches its greatest apparent height for the first place is one hour ahead of the second. Time zones refer to the apparent motion of the sun, not the motion of the earth. So they are calculated as solar day divided by 360 degrees. Put another way, the ...


28

We teach the students: Sidereal day: In 23 h 56 min the earth rotates 360° Solar day: In 24 h the earth rotates 361° You should not teach your students that. You should instead teach your students that it takes the Earth 23 hours and 56 minutes to rotate 360° with respect to the remote stars. So why do we use a 24 hour day? The reason we use a 24 hour day ...


9

Here’s a slightly different way to think about it that might be helpful to you and/or the students. To answer the question “how long does it take the Earth to rotate once on its axis?” you have to first answer “rotate with respect to what reference point?” If you ask how long it takes to rotate enough to bring a given star back to the same position, that is ...


52

The Earth takes 23 hours 56 minutes to rotate once. But that is not relevant to most people. Sure, the stars will be in the same position again after 23 hours 56 minutes, but the sun will not be in the same position. It is far more important, for most people, to measure the time from noon to noon. And the average time from noon to noon is 24 hours. This is ...


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