= Heliocentric model
= Heliocentrism
{synonym}
A <heliocentric model> places <Earth> and the other <planets> in <orbits> around the <Sun>. The apparent annual journey of the <Sun> through the <celestial sphere> then reflects <Earth>'s own orbital <motion>. Apparent backward loops in a <planet>'s path can arise from viewing its <motion> from another moving <planet>.
The geometric arrangement alone does not specify the shape or governing <force> of an <orbit>. <Nicolaus Copernicus> used combinations of <circular motion>; <Johannes Kepler> subsequently described <elliptic orbits>. Distinguishing a reference arrangement, a mathematical trajectory and a physical explanation prevents these separate achievements from being conflated.
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