1. Teacher notes
This ordering activity could be used as a plenary or revision exercise on the lifecycle of small stars, and the difference between small stars and large stars in the following activity. Mini-whiteboards could be used to make this a whole-class exercise.

2. Teacher notes
This ordering activity could be used as a plenary or revision exercise on the lifecycle of large stars, and the difference between large stars and small stars in the previous activity. Mini-whiteboards could be used to make this a whole-class exercise.

3. Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.

4. What might lead scientists to question this model?
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
The Steady State Theory
The Universe has always existed and always will.
This is based on the fact that the Universe appears pretty much the same everywhere and always has done. The apparent expansion of the Universe is explained by suggesting that new matter is being created
What might lead scientists to question this model?

5. Cosmic microwave background
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
Learning Objectives
By the end of this lesson you should…
Know the evidence that must be explained by a theory of the Universe
Understand the term red shift
Be able to describe the alternative theories of the Universe
Three observed features of the Universe which disprove the steady state:
Cosmic microwave background
Light from other galaxies is red-shifted
The further away a galaxy is, the greater its red-shift

6. In 1964, two unsuspecting scientists made a discovery so large they didn’t even realise!
antenna
Penzias
Wilson
Penzias and Wilson, two physicists from the Bell labs, who would later win the Nobel prize in 1978 for their work.

7. Cosmic Microwave Background
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
Cosmic Microwave Background
CMB is radiation remaining from the Big Bang explosion and fills the whole of the Universe.
This radiation has cooled as the Universe has expanded and is now slightly less than 3 degrees above absolute zero.
Discovering about the CMB

8. Cosmic Microwave Background
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
Cosmic Microwave Background
Where ever we look we measure the same data. So, the big-bang must have taken place at the same time everywhere.
Discovering about the CMB

9. Look at the light coming from our Sun
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
Look at the light coming from our Sun
- Use a spectroscope to view the light coming in through the window

10. If you pass the light through a gas something different is seen…
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
helium
Some wavelengths of light are absorbed by the gas – an “absorption spectrum”.

11. It is red - shifted Before After Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
If the light source is moving away the absorption spectra look a little different…
Before
After
It is red - shifted

12. Lets think about sound…
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
Why?
Lets think about sound…
What noise does a motorbike moving away from you make?

13. Teacher notes
This four-stage animation explains the Doppler effect using sound.

14. The Doppler Effect Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
The Doppler Effect A B B A
Source of waves is moving to the right
Source of waves is stationary
A hears a sound with a long wavelength (low pitch). B hears a sound with a short wavelength (high pitch)
A and B hear the same sound

15. Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
As a car approaches us the sound waves are _________ together. We hear _____ waves per second and so the frequency is greater (_______ pitch).
As a car moves away the sound waves are ________ out. We hear less waves per second and so the frequency is lower (_______ pitch).

16. Light sources in the Universe are moving away from each other
The same happens with light waves.
For a light source moving away from us we will observe longer wavelengths
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
Before
After
Light sources in the Universe are moving away from each other

17. This means the distant galaxies must be moving away from the Earth.
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
This means the distant galaxies must be moving away from the Earth.
Photo credit: © 2006 Jupiterimages Corporation
It has also been observed that the further away a galaxy is, the greater the amount of red shift.
This means that very distant galaxies must be moving faster than near.

18. Light from other galaxies has a longer ____________ than expected
Light from other galaxies has a longer ____________ than expected. This shows that these galaxies are moving _______ from us very quickly.
This effect is seen to a greater extent in galaxies that are _________ away from us. This indicates that the further away the galaxy is, the ________ it is moving. This shifting of light towards the red end of the spectrum is called the ‘____ _____’. (Note that objects coming _______ towards us will experience a shift towards the blue end of the spectrum.
This evidence seems to suggest that everything in the universe is moving away from everything else, and that this process started around 15 _____ years ago. This is the ____ ________ Theory.

19. Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
The Big Bang Theory
About 15 billion years ago, all the matter in the Universe was compressed into a very small space and exploded.
It is believed that the background radiation is a residue from the explosion.

20. Consequences
If everything is moving away from us and things farther are moving faster
Then the Universe is expanding!
This doesn’t mean what you are probably thinking

21. Expanding Universe
Space itself is expanding, not matter flying apart within space.
Examples:
dots
rubber band
raisin bread
ants on a balloon
It does not mean we are at the center of the Universe
every part of the Universe sees everything moving away from it

22. The Universe from beginning to end
Teacher notes
This six-stage sequence introduces the different theories about the beginning and end of the Universe.

23. What are the possible fates of the Universe?
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
What are the possible fates of the Universe?
Low mass
High mass

24. Work through ‘The Universe’ worksheet
Learning Objectives
By the end of this lesson you should…
State the evidence for the big bang and explain why alternative theories are insufficient.
Explain what is meant by the Doppler effect
Describe how the light from distant stars may be red-shifted and explain the implication of this on our understanding of the universe.
HOMEWORK
For next lesson
Work through ‘The Universe’ worksheet

25. Cosmic Microwave Background Radiation (CMBR) was discovered by scientists in It is a form of electromagnetic radiation that fills the universe.
Where do scientists believe CMBR came from? [1]
CMBR is used to support the Big Bang theory. How does the Big Bang theory describe the beginning of the universe? [1]
Red shift is a piece of evidence used to support the Big Bang theory. Explain how red shift provides evidence to support the Big Bang theory [6]