Describe the Nicolaus Copernicus model for planetary motion.

(N/A) Nicolaus Copernicus proposed the heliocentric model of the solar system in the $16^{th}$ century. The key features of his model are:
$1$. The Sun is at the center of the solar system,and all planets,including the Earth,revolve around it in circular orbits.
$2$. The Earth is not stationary; it rotates on its own axis once every $24$ hours,which explains the apparent daily motion of the stars.
$3$. The Earth also revolves around the Sun once every year.
$4$. The apparent retrograde motion of planets (where they seem to move backward in the sky) is explained as a natural consequence of the Earth overtaking slower-moving outer planets in their orbits.