CHAPTER 3

What question was Edwin Hubble trying to answer? P 43

How did Hubble find the distance to the Andromeda Nebula? P44

How is parallax used to measure distances? P 44

What was Henrietta Leavitt’s technique for measuring distances? P 45

When you look at the Andromeda galaxy (you can see it with a telescope), when did the light leave it? P 45

What was happening on to humanity at that time? P 45

What’s the Doppler effect? P 47

What is the galactic redshift? P 50

What did Hubble conclude about the galactic red shift? P 50

Are the galaxies moving through space? P 52

What does the picture on page 53 show?

What is another explanation (other than Doppler) for the red shift? p 57 58

What are the most abundant elements in the universe? P 58

Where does the Sun get its energy? P 59

What’s an isotope? P 62

What was Gamow’s view of the Big bang p 62

What was Alpher and Herman’s prediction about the Big bang, and why did they make it? P 63, 64