Nicolaus Copernicus "Almagest" circa 150 CE; the Earth was the stationary center of the universe. Stars were embedded in a large outer sphere which rotated rapidly, approximately daily, while each of the planets, the Sun, and the Moon were embedded in their own, smaller spheres. Ptolemy's system employed devices, including epicycles, deferents and equants, to account for observations that the paths of these bodies differed from simple, circular orbits centered on the Earth. Copernicus' major work on his heliocentric theory was "Dē revolutionibus orbium coelestium" ("On the Revolutions of the Celestial Spheres"), published in the year of his death, 1543. He had
Allegory of the Planets and Continents orbiting the Sun. The cornice of the painting symbolize the continents Europe, America, Africa, and Asia. Allegory of the Planets and Continents Allegory of the Planets and Continents is an 18th-century painting by Italian artist Giovanni Battista Tiepolo. Done in oil on canvas, the allegorical work uses human figures to represent members of the Greco-Roman pantheon, the planets, and four continents. The painting is an elaborate oil sketch made by Tiepolo in preparation for rendering a similar, larger version of his scene. Tiepolo's work was painted to be hung above a staircase of the Wurzburg Residence in Wurzburg, Germany. The