# Redshift is observed in light from distant galaxies. Describe what redshift is and explain what it tells us about how galaxies are moving, including how the speed of recession relates to distance.

> Cambridge International IGCSE Physics (0625) — 6.2 Stars and the Universe · Describe · 4 marks

## Mark scheme (4 marks)

1. Redshift is an increase in the observed wavelength of electromagnetic radiation (light) emitted from a galaxy
2. Redshift occurs because the galaxy is receding / moving away from Earth
3. Galaxies that are further away show greater redshift / are receding faster
4. This evidence supports the idea that the Universe is expanding

## Key terms

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

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Source: [GradeNine](https://www.gradenine.co.uk/q/redshift-is-observed-in-light-from-8033ce3f) · Published by Druglandscape Ltd.