# Describe how our understanding of the Solar System has changed over time, from an Earth-centred model to a Sun-centred model, and state one piece of evidence that supports the Sun-centred model.

> Eduqas A-Level Physics — 4.3 Orbits and the wider universe · Describe · 5 marks

> For centuries, scientists believed that the Earth was at the centre of the Solar System. This view was eventually replaced by a model in which the Sun is at the centre.

## Mark scheme (5 marks)

1. Early model placed the Earth at the centre of the Solar System (geocentric model)
2. The model was changed / replaced so that the Sun is at the centre (heliocentric model)
3. The change in model was driven by new observations / evidence that the old model could not explain
4. Correct identification of a piece of supporting evidence for the Sun-centred model — e.g. the phases of Venus
5. Correct explanation of why that evidence supports the Sun-centred model

## Key terms

- [evidence](https://www.gradenine.co.uk/glossary/evidence)

## Related

- [Revision notes for Eduqas A-Level Physics](https://www.gradenine.co.uk/learn)
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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-how-our-understanding-of-the-cecc9018) · Published by Druglandscape Ltd.