Explain why diurnal motion is counterclockwise for a star we observe toward the north but clockwise for a star?

Question

Explain why diurnal motion is counterclockwise for a star we observe toward the north but clockwise for a star we observe toward the south.

Answer 1

Imagine you are looking at a clock . The front and back are transparent, but the hands and numbers are opaque. When you look at the clock from the 'front' the hands move clockwise. When you look at it from the back, the hands move counterclockwise, even though the hands are moving in one direction the entire time, your reference point matters.



Now, change the previous terms into the following:



Clock = Earth

Standing in front of the clock = looking down on Earth from above the south pole

Standing behind the clock = looking down at the Earth from above the north pole

Answer 2

Stars move across the sky in the same direction. All that changes when you are facing north and then you turn around and face south is your PERSONAL coordinate system. When you face north, west is to your left and east is to your right. When you face south, west is to your right and east is to your left. When you face north, clockwise motion is toward your right hand, so the stars are moving in an anti-clockwise direction, but when you turn around, and face south, clockwise motion is to the west, the same direction that the stars seem to be moving, becasue Earth rotates west to east with respect to the celestial sphere.

Answer 3

Is it because of the rotation of the earth? If you are on a large sphere rotating in one direction and you look north, the stars will appear to move either clockwise or counterclockwise and if you look south, they will appear to move in the opposite direction...?