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 War of the Worlds the 20th Century, including first contact and war between planets and their differing species. There were, however, stories of aliens and alien invasion prior to publication of "The War of the Worlds". In 1727 Jonathan Swift published "Gulliver's Travels". The tale included a people who are obsessed with mathematics and more advanced than Europeans scientifically. They populate a floating island fortress called Laputa, 4½ miles in diameter, which uses its shadow to prevent sun and rain from reaching earthly nations over which it travels, ensuring they will pay tribute to the Laputians. Voltaire's "Micromégas" (1752) includes two beings from Saturn