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
Earth, Moon, and Planets Earth, Moon, and Planets Earth, Moon, and Planets is a peer-reviewed scientific journal, published approximately ten times per year by Springer Science+Business Media. It was established in 1969 under the title "The Moon", was known as "The Moon and the Planets" from 1978 to 1983, and was first published under the current title in February 1984. The editor-in-chief is Murthy S. Gudipati (Caltech and JPL). The journal's main focus is on research about the Solar System. Besides original research articles, "Earth, Moon, and Planets" publishes conference proceedings, review articles, book reviews, and special issues. "Earth, Moon, and Planets" focuses on