Orrery on display in Kassel at the Astronomisch-Physikalisches Kabinett and in Dresden at the Mathematisch-Physikalischer Salon. In "De revolutionibus orbium coelestium", published in Nuremberg in 1543, Nicolaus Copernicus challenged the Western teaching of a geocentric universe in which the Sun revolved daily around the Earth. He observed that some Greek philosophers had proposed a heliocentric universe. This simplified the apparent epicyclic motions of the planets, making it feasible to represent the planets' paths as simple circles. This could be modelled by the use of gears. Tycho Brahe's improved instruments made precise observations of the skies (1576–1601), and from these Johannes Kepler
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