Here's why:
* Gravity: The Sun is much more massive than Earth, and its gravity pulls on Earth, keeping it in orbit.
* Inertia: Earth has inertia, which means it wants to continue moving in a straight line. However, the Sun's gravity constantly pulls it back, causing it to move in a circular path (actually slightly elliptical).
* Apparent motion: From our perspective on Earth, the Sun appears to move across the sky. This is because Earth is rotating on its axis, giving us the impression of the Sun rising in the east and setting in the west.
So, the Sun doesn't move around the Earth; it's Earth moving around the Sun, causing the apparent movement we see!
