Physics – 6.1.1 The Earth | e-Consult

The Earth is a sphere that rotates on its axis, an imaginary line running through the North and South Poles. This rotation takes approximately 24 hours to complete one full cycle. As the Earth rotates eastward, different locations on the planet are gradually brought into view of the Sun.

From our perspective on Earth, it appears as though the Sun is moving across the sky. However, this is an illusion caused by our own rotation. As a specific location on Earth rotates towards the Sun, the Sun appears to rise above the eastern horizon. As that location continues to rotate, the Sun appears to move higher in the sky. Eventually, that location rotates away from the Sun, and the Sun appears to set below the western horizon. The Earth's eastward rotation is the fundamental reason for this apparent daily motion of the Sun.