Text: A "Day" on Earth 1. Have student 2 rotate once counterclockwise, begin facing the Sun and rotate until they are facing the Sun again --- they have rotated once. For the Earth this is 23 hours 56 min 4 sec. 2. Now have student 2 do the same thing, but have them revolve slowly around the Sun at the same time (see Figure 2). In order for them to end up facing the Sun again, they have to rotate a little bit more than once. Therefore, the time from noon to noon, when the Sun is overhead (24 hours or one day), is slightly more than the time it takes the Earth to rotate on its axis. 3. This is why we see different stars at different times of the year. The stars are like seeing different parts of the room as we rotate on our axis and revolve around the Sun.

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