Return to 8 Astrophysics – Part A “Units”

8 Astrophysics – Part D “Cosmology”

Aims… (Triple Only)

8.13P describe the past evolution of the universe and the main arguments in favour of the Big Bang

8.14P describe evidence that supports the Big Bang theory (red-shift and cosmic microwave background (CMB) radiation)

8.15P describe that if a wave source is moving relative to an observer there will be a change in the observed frequency and wavelength

8.16P use the equation relating change in wavelength, wavelength, velocity of a galaxy and the speed of light:

Change in wavelength/reference wavelength = velocity of a galaxy/speed of light

λλ0λ0  =vcλλ0 =vcλλ =vc


8.17P describe the red-shift in light received from galaxies at different distances away from the Earth

8.18P explain why the red-shift of galaxies provides evidence for the expansion of the Universe.



Video Clips…

Cosmic Microwave Background Explained

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BEEN BLACK? As long as we've been around, YES. But the universe gets much more exciting, AND much BRIGHTER, as we start winding our clocks back to the early days of the universe. Near the beginning of the universe, when space was rapidly expanding, that dark night sky we know so well as actually…ORANGE! But why? Did the lights just go out, or did something more spectacular happen? Watch this episode of PBS Space Time and find out!

Extra Credit:
CMG Scissored Pair


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