The Celestial Spheres model was ancient Greece's attempt at making the universe user-friendly, plotting the heavens as if they were a series of celestial nesting dolls with Earth cosily tucked in at the centre. This geocentric viewpoint, endorsed by intellectual influencers du jour (Aristotle and Ptolemy) positioned the stars, planets, and other celestial bodies on these spheres, moving in perfect harmony around our planet. This theory held sway for centuries, even after Copernicus reimagined the cosmos with the Sun at the core.

New versions of the celestial sphere model were introduced, with the planetary spheres following this sequence from the central Sun: Mercury, Venus, Earth-Moon, Mars, Jupiter and Saturn. However, with the Scientific Revolution, mainstream belief in celestial spheres waned, replaced by Newton's law of universal gravitation and Newtonian mechanics.