Diurnal Motion (with Equatorial Coordinate System)


Diurnal Motion

Fix the camera towards the Polaris at night. When you shoot for a few hours in that state, you can see the stars move in a circle around the Polaris.
The movement of these stars appears because the earth is rotating.

The sun and the Moon also have Diurnal Motion due to the Earth’s rotation. Day and night occur because the earth rotates.
Also, the orbit of a satellite that circles around the earth moves a little bit to the west every time it returns, and this phenomenon is caused by the rotation of the earth.