Red-Shift and the Expanding Universe | GCSE Physics
Red-shift provides evidence that the universe is expanding and that galaxies are moving away from us.
If a galaxy shows more red-shift, is it moving faster or slower?
What is Red-Shift and the Expanding Universe | GCSE Physics?
"The displacement of spectral lines toward longer wavelengths (the red end of the spectrum) in radiation from distant galaxies and celestial objects."
Expanding Evidence
Light from distant galaxies is shifted towards the red end of the spectrum.
Greater red-shift means the galaxy is moving away faster.
Distant galaxies are moving away faster than nearby ones.
This supports the idea that space itself is expanding.
Sound Link: Red-shift is like the change in pitch of a siren passing you (Doppler Effect), but with light waves instead of sound.
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