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1000 BCE
The ancient Egyptians
Bottom-land on it — the goddess of the sky; left and right — the Sun God's ship, showing the path of the Sun across the sky from sunrise to sunset. -
500 BCE
The ancient Greeks
The ancient Greeks imagined the Earth flat.They considered it a flat disk surrounded by inaccessible to man sea. -
168
Ptolemaic model
In the second century CE, Ptolemy, who lived in the Egyptian town of Alexandria, produced a mathematical representation based on observation of the known Solar System. In Ptolemy’s model, the Earth was at the centre of the Universe, with the Sun and planets revolving in a series of circular orbits moving out from the Earth. This model became known as the ‘geocentric’ model. -
1543
Copernican model
Nicolas Copernicus (1473–1543) was a Polish scholar who reconstructed Ptolemy’s model of the Universe Copernicus was able to simplify the system by switching from an Earth-centred model to a Sun-centred one. -
Johann Kepler
German astronomer who worked for Brahe and used his measurements to calculate that planetary orbits were elliptical (AKA ovals) and not perfect circles as previously thought. -
Galileo Galilei
Italian scientist who disproved the geocentric model by using a telescope to demonstrate that Jupiter had its own moons. By proving that the moons moved around Jupiter and not Earth, it made it clear that the geocentric model, where everything orbits the Earth, was incorrect. -
Sir Isaac Newton
British mathematician and scientist who developed the theory of universal gravitation, which explained why the planets orbited the Sun in elliptical orbits, confirming Kepler's work. -
New Planets
Uranus -
Neptune
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Pluto
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Dwarf planet
Although later in 2006 it was decided to call Pluto a dwarf planet.
