De revolutionibus orbium coelestium have begun work on his new system by that time. Most historians believe that he wrote the "Commentariolus" after his return from Italy, possibly only after 1510. At this time, Copernicus anticipated that he could reconcile the motion of the Earth with the perceived motions of the planets easily, with fewer motions than were necessary in the "Alfonsine Tables", the version of the Ptolemaic system current at the time. In particular, the heliocentric Copernican model made use of the Urdi Lemma developed in the 13th century by Mu'ayyad al-Din al-'Urdi, the first of the Maragha astronomers to develop a non-Ptolemaic
The Shadow of the Sun rural villages which gave him an honest perspective on what was the current situation of the continent. The Shadow of the Sun The Shadow of the Sun (, literally "Ebony") is a travel memoir by the Polish writer and journalist Ryszard Kapuściński. It was published by Penguin Books in 2001 with the English translation by Klara Glowczewska. Kapuściński spent nearly 30 years in various African countries such as Kenya, Rwanda, Nigeria, Ethiopia and more, detailing his accounts as a white, foreign visitor, of the development of the African states. Kapuściński's experience in Africa was unique, because he had the opportunity