Astronomy 201 - Study questions for the Final Exam.	Winter 1993 - Sullivan

NOTE:  You are responsible for all the lectures and films, as well as the
       portion of the reading in the text that was specifically required
       (Chapters 7 and 8).  Anything in that body of material is fair game,
       whether or not it appears here on the study sheet, but we have tried
       to make this complete.  Don't forget to bring a mark-sense form to
       the Final Exam on Wednesday at 1:30 pm in the normal lecture hall
       in Savery.

Part I - Cosmology
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We think H is 15 km/s per million light years.  If it were 30 km/s/Mly, how
would our estimate for the age of the Universe change?

If Galaxy A is twice as far away as Galaxy B and expanding according to 
the Hubble relation, how much faster will it be moving relative to B?

Why doesn't Hubble's Law work on small scales, like within the Milky Way
or the solar system?

How do you explain the distribution of galaxies (both ends of the distribution
as well as the peak in the middle) in the data set for lab #1?

What would the Hubble relation look like if there were no large scale
motion in the Universe?  If the Universe were contracting?

What is Newton's paradox and what do we conclude from it?

What is Olbers' paradox and what do we conclude from it?

What is the Cosmological Principle?  The Perfect Cosmological Principle?
(be sure you understand that these are _not_ observations, but assumptions).

What are a couple of reasons we think the P.C.P. is not valid?  Explain!

What type of cosmology does the P.C.P. support?

What is the difference between a scientific and "ad hoc" model?

What are a couple of observations predicted by General Relativity?

What is the difference between Special and General Relativity?

How does the speed of light vary relative to how fast you are moving?

What is the principle of equivalence?

What is the Anthropic principle?

What exactly _is_ the Microwave Background Radiation (MBR)?

Why is the MBR hotter in one direction and cooler in the opposite direction?

How does the temperature of the MBR change as we go back in time to, say,
a tenth the age of the Universe?  A hundredth?

Why can't we see radiation from interesting early times such as the
first three minutes?

What is the critical density of the Universe?  What happens if the density
of the Universe is greater than the critical value?  Less than?  Equal to?

How much visible matter do we see in the Universe (what is the density
of visible matter with respect to the critical density)?

Why is dark matter so important for having a "flat" Universe?

What happens to a circle and triangle in the three different geometries
(closed, flat and open)?  What about parallel lines?

What are two pieces of direct evidence that support the existence of 
dark matter?

What else was going on when the MBR was released?

List in order the 7 or 8 major events in the history of the early
Universe (start with inflation, end with the release of the MBR).

Why do we even bother with inflation?  What problem does it solve?

What were the three important factors that determined how well 
nucleosynthesis worked?

What were the three major constituents of the Universe after the
first three minutes?  (Hint:  One is Deuterium)

What are neutrinos and why might detecting them be important for the
study of the early Universe?

How does the matter density compare to the radiation density today?
What about at an age of 3 minutes?  100,000 years?

What is the Planck time and why is it important?

Part II - Galaxies and Stars
----------------------------
What is the main difference between stars in elliptical galaxies vs.
stars in spirals (Hint:  The same question could be asked about the
difference of halo stars vs disk stars in our own Milky Way)?

What caused the differences between Ellipticals and Spirals?

How does the presence or absence of heavy elements in a star help
us to decide whether there might be life there?

What are some of the requirements a stellar system (stars and planets)
must meet in order for life to develop?

What is the _apparent_ distribution of stars and galaxies in the Milky
Way, as seen from Earth?  What causes this?

What is the _actual_ distribution of stars and galaxies as seen from Earth?
(Know the meanings of the words "homogeneous" and "isotropic").

Why do only the most massive stars go supernova?

How does the heavy element content of stars in a spiral galaxy change
with time?  What is the source of the changes in the ISM (two major
sources)?  ISM = Inter-Stellar Medium

Why do massive stars live shorter lifetimes than less massive stars?

What role does iron fusion play in a supernova?  What does this imply
about finding any elements in the ISM that are heavier than iron?

What are the basics of stellar evolution (i.e. what happens to a star
when it runs out of Hydrogen in the core?  Helium?) and how does
stellar evolution (or why does it) depend on mass?

What phase of the early Universe do stellar cores most resemble?  How
can we deduce that?


Part III -- Solar System
------------------------
How do we know how old the solar system is?

Where did the water on Earth come from?

Why don't Venus and Mars have liquid water?

Why does the composition of Earth differ so much from the Sun?  Why is
Jupiter's composition so close to the Sun's?

How does the Moon influence the development of life on Earth?

Be able to do a numerical example of radioactive dating.

How did the runaway greenhouse effect get started on Venus?

What is the major process that removed Carbon Dioxide from Earth's
primordial atmosphere?

Why did Mars lose most of its atmosphere?

How does the greenhouse effect relate to the "Faint Sun Paradox"?

What are some examples of greenhouse gasses and how does the greenhouse
effect work specifically?

What are some important planetary characteristics that determine what
the composition of the atmosphere will be?

What are the five phases of the "Carbon Cycle"?

How can water vapor serve to both increase and decrease the temperature
on Earth?

Part IV - Life
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How is evolution related to selection pressure?

What is the theory of natural selection?  Is natural selection driven
by some "need" to evolve, or is it largely governed by random mutations?

What is some _direct_ evidence that supports evolution?  (Hint: the
"perfect" design of a hummingbird is not direct evidence.)

What are the factors that led to increases in diversity among species?
What factors have altered this trend of increase?

What are some of the specific requirements a planet must meet in order
to develop life as we know it?

What properties does DNA have that or important for life?

What is it about Silicon that makes it a plausible foundation for
the development of life?

Why are Carbon-based life forms favored over Silicon-based life forms?

What were the first forms of life for which we have fossil evidence
and what role did they play in the development of later life?

What were some of the important evolutionary steps and selection pressures
in the early history of man?

What was the Miller-Urey experiment, and what did it show?

How many different DNA bases are there?  How many amino acids does the
human body require?  How can you use this information to determine how
many different bases must combine to form the minimum number of unique
amino acids our body requires?

What are the chances of a specific amino acid forming from a random
collection of bases?  What about the chances of a specific chain of
100 bases (RNA) forming spontaneously from a random pool of bases?

What are the characteristics needed in order for an entity to be
considered to be alive?

How has Oxygen played a role (or not played a role) in the development
and evolution of life on Earth?

Why is water so important for life as we know it?

What caused the mass extinction of 65 million years ago, and what evidence
do we have to support the best theory?

What was the Earth like before the KT event, and why was the KT event
so catastrophic?

What are some of the characteristics of the life found around the deep
sea hydrothermal vents?

What is the Drake equation, and what number specifically is it trying
to find?

Which of the terms of the Drake equation do we know well?  Which do we
have a chance of finding out in the near future?

What is the assumption of mediocrity?

Why is radio communication so much easier than physical communication
among two intelligent species living far away from one another in the
Galaxy?

What are some of the problems we have in trying to find out where in
the electromagnetic spectrum to look for extraterrestrial signals?  How
do we try to get around these problems?

What are some examples of evidence that would point to the existence
of another civilization around a star?