ISP 205 Lab 12 Discussion Questions

  1. Why do you think it has been so difficult for astronomers to determine the value of the Hubble constant?

  2. Calculate the maximum age of the universe for a Hubble constant of 50, 75, and 100 km/s/Mpc. In view of your answers, explain how the ages of globular clusters could be used to place a limit on the maximum value of the Hubble constant.

  3. The so-called creationists claim that the universe came into being about 6000 years ago. What are possible arguments for and against this view?

  4. In lab 10 you studied HR diagrams and properties of hot and luminous stars as well as cool and dim stars. Given the age of the universe considered most likely by astronomers, why are all of the K and M type stars formed at the beginning of the universe still on the main sequence. What has happened to the O and B type stars that formed at the beginning of the universe?

  5. Since gravity is attractive, after the big bang we would expect that the expansion of the universe is gradually slowing down. After looking at galaxies further and further away (further back in time) we find that the opposite is true. The expansion of the universe is speeding up. What does this mean? What might be causing this? This is an unresolved problem in astronomy today, and there are no right or wrong answers. Come up with a couple of theories and discuss the strengths and weaknesses of them.