Astr 328 Midterm Exam Questions (2006 edition)
There will be three questions taken
from this list. You should plan on spending ~ 2-3 bluebook pages
answering each one.
- Why do we need to study relatively distant
galaxies to get a get a measure of the Hubble constant? Why can't we
just use distances to nearby galaxies, where Cepheids give us good
distances, to measure H0?
- Describe several reasons why high redshift
galaxies might look different from galaxies in the local universe.
- Describe the "surface brightness fluctuation"
technique for finding distances to galaxies. Is this technique better
for spirals or ellipticals? Why?
- Write down the Friedmann equation, and describe
each term. Using the Friedmann equation, derive the following
for an Omega=1, Lambda=0 universe.
- R(t)
- t(z)
- the current age of the Universe
- Explain the test behind the supernova
cosmology
project,
and the recent results from this project.
- Describe what we mean by "peaks" in the power
spectrum of
the microwave background. What causes these peaks, and what do they
tell
us about the Universe?
- Describe how globular cluster ages are
determined, and how these ages constrain the cosmological parameters
which describe the universe. Be specific!
- Describe the four classical tests of cosmology,
and what data you might need for each one. Explain which of the tests,
if any, are providing good tests of cosmology today.
- Describe the Tully-Fisher relationship (including
its physical implications). Discuss the data you need to measure H0
with Tully-Fisher, and explain how the cluster incompleteness bias can
influence your answer.
- Describe the five foundations of modern
cosmology.