Models are useful for helping us to think, understand, remember and predict.
In the ancient Greeks' model of the whole Universe, the Earth was at the centre. In this model, the Earth is fixed and everything else orbits around it. Up until 400 years ago, most people thought this, the geocentric model, provided a true picture of the way the Universe worked.
Then, astronomers such as Copernicus and Galileo publicised a new model, with the Sun at the centre of the orbits of all of the planets (including the Earth). The new ideas were called the heliocentric model.
The geocentric model was based on ancient writings. The heliocentric model was based on observations. This switch in belief was a BIG change and caused problems as the highly religious climate in which Copernicus and Galileo worked centred on the belief that God had created the Earth at the centre of the Universe.
New observations showed that:
- The heliocentric model provided better predictions of the movements of the planets.
- Everything in the Universe does not go around the Earth.
Read more on the Solar System here
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