Geocentric model and planets were holes in invisible wheels surrounding Earth; through the holes, humans could see concealed fire. About the same time, Pythagoras thought that the Earth was a sphere (in accordance with observations of eclipses), but not at the center; they believed that it was in motion around an unseen fire. Later these views were combined, so most educated Greeks from the 4th century BC on thought that the Earth was a sphere at the center of the universe. In the 4th century BC, two influential Greek philosophers, Plato and his student Aristotle, wrote works based on the geocentric model.
Central City, Nebraska school. In the 1950s, Nebraska Central College closed (1953) but a new hospital was built in 1959. In 1975, an explosion and fire destroyed an entire city block, but Central City still reached its largest population to date at 3,083 people in 1980. Central City's population has declined slightly since then. Six places in or near Central City are listed in the National Register of Historic Places. To qualify for listing in the National Register of Historic Places, a place (e.g., building, landmark, or location) must be at least 50 years old and have one or more of the following