Timeline of astronomy Rectification of Planetary Theory", eliminated the need for an equant by introducing an extra epicycle, departing from the Ptolemaic system in a way very similar to what Copernicus later also did. Ibn al-Shatir proposed a system that was only approximately geocentric, rather than exactly so, having demonstrated trigonometrically that the Earth was not the exact center of the universe. His rectification is later used in the Copernican model. Nicolaus Copernicus publishes "De revolutionibus orbium coelestium" containing his theory that Earth travels around the Sun. However, he complicates his theory by retaining Plato's perfect circular orbits of the planets. A brilliant
The empire on which the sun never sets Empire". From the mid-nineteenth century, the image of the sun never setting can be found applied to Anglophone culture, explicitly including both the British Empire and the United States, for example in a speech by Alexander Campbell in 1852: "To Britain and America God has granted the possession of the new world; and because the sun never sets upon our religion, our language and our arts...". By the end of the century, the phrase was also being applied to the United States alone. An 1897 magazine article titled "The Greatest Nation on Earth" boasted, "[T]he sun never sets on Uncle