Receding Galaxies (GCSE Physics)
Receding Galaxies
Red Shift and Receding Galaxies
Evidence for Receding Galaxies
We have learnt that red-shift provides evidence for galaxies moving away from each other. ’Receding’ is simply another way of saying this.
- The further away the galaxies are, the more quickly they are receding. We can use red-shift to determine how fast a galaxy is moving away from us. The larger the red-shift of a galaxy, the faster it is moving away from us. Distant galaxies will have a large red-shift, since they are receding most quickly.
Evidence for Expansion
The speed of a galaxy will be determined by its distance from us. The closer a galaxy is to us, the slower it will move. The further away it is, the faster it will move.
We have just mentioned that galaxies that are furthest away from us will move the fastest. Since they are moving, space (and therefore the universe) must be expanding.
Still got a question? Leave a comment
Leave a comment