–The
exam will be similar in format to the midterm.
Roughly 1/3 of it will focus on the same material that was tested on the
midterm, the other 2/3 will cover everything else.
–You
will be given all formulas and most numerical constants and conversion factors
(the exception: you must know what prefixes like mega- or nano- mean). You must bring a calculator with you to
the exam!
–You
may not consult notes or textbooks during the exam, or give or receive aid in
any way. As always, the Connecticut College Honor Code applies to all aspects
of the exam; in particular, once you take the exam, you may not discuss
anything about it with students who have not yet taken it.
–The
following are a list of topics and questions that we have studied since the
midterm. It is not an exhaustive list, nor will all of these topics necessarily
appear on the final. It is simply meant as a way to help guide your studying.
You should also review the end-of-chapter problems, the quizzes, the midterm
review sheet, the midterm exam, and your notes.
What
are the two types of telescopes? What
are the three powers of a telescope? Of
the seven kinds of light that make up the electromagnetic spectrum (i.e.: R M I
V U X G), which two types can be detected by telescopes on the ground? What blocks the other five kinds of light
from reaching ground-based telescopes?
For what reasons were the Hubble Telescope placed in space?
Know
what the ISM is, what it is made of, and how it is related to
star-formation. What is an emission
nebula / H II region, and by what process does it glow? What are reflection nebulae and dark nebulae
/ Barnard objects / Bok globules, and how do they imply the presence of dust in
the ISM? What are interstellar
reddening and interstellar extinction, and why do they occur? What kinds of “triggers” initiate the
formation of protostars from clouds in the ISM? Describe the evolution of a protostar into a main-sequence
star. How does the mass of a protostar
affect its evolution? What is an open
cluster? Understand what the H-R
diagrams in Figures 20-17b and 20-18b tell you about the relative ages of NGC
2264 and the Pleiades, and why.
What
two opposing forces just balance within a main sequence star, and what happens
to the star if that balance is upset?
When a gas contracts or expands, how do its pressure and temperature
change? What types of nuclear fusion
can go on in the cores of main-sequence and post-main-sequence stars, and what
determines the temperatures needed for these reactions to occur? What is the relationship between a star’s
mass and its main-sequence lifetime, and why?
What is the main-sequence turn-off point, and how can we use it to
determine the age of a star cluster?
What is a globular cluster?
Know
the major stages in the post-main-sequence evolutions of both low-mass (< 4
Mo) and high-mass (> 8 Mo) stars. During each of these stages, you should be
able to say a) what the core and envelope of the star are doing, b) what kinds
of nuclear fusion reactions are going on, and where in the star they are taking
place, c) where stars in each stage are located on an H-R diagram. Be able to draw rough sketches of the
evolutionary tracks for both low-mass and high-mass stars. What are the heaviest elements made via
fusion reactions in the cores of stars, and why does no further fusion take
place (note: the answers to these questions are different depending on whether
you are discussing low-mass stars or high-mass stars)?
What
are Population I and II stars, and what do they tell us about the history of
star-formation in the universe? What
are RR Lyrae stars and Cepheid stars?
Where are they found on an H-R diagram?
Why are they useful for measuring distances, and what does the inverse
square law of light have to do with this?
What is the period-luminosity relationship for Cepheids, and why is it
important?
Know
about the following end-states of stars: planetary nebulae, supernova remnants,
white dwarfs, neutron stars, black hole singularities. What are the properties of these
objects? Which of these come from
stellar cores, and which from stellar envelopes? Which from low-mass stars, and which from high-mass stars? What is degenerate pressure (two kinds), and
in which of these objects is this concept important? Which of these objects have minimum or maximum masses, and what
are those mass-limits? What are Type Ia
and Type II supernovae?
What
is a pulsar, and how is it like a lighthouse?
What is conservation of angular momentum, and how does it explain why
pulsars rotate so quickly? What is
escape velocity, and how does this concept relate to black holes? What is an event horizon, what do we call
its radius, and how do you calculate that radius? How do astronomers discover black holes (hint: binary systems)?
What
is the difference between a solar system, a galaxy, and a universe? What is “the band of the Milky Way”? How did dust fool astronomers into thinking
that we were at the center of our Galaxy, and how did we discover that we
weren’t (hint: globular clusters)?
Know
the three components of our Galaxy (disk, bulge, halo), and the properties of
each. Where are Pop I and II stars found
in our Galaxy, and why? Where does
star-formation currently take place in our Galaxy, where does it not currently
take place, and how do we know? You
should be able to use the version of Kepler’s Third Law presented on page 441
of your book, to find masses of objects and/or masses within orbits. What is a rotation curve? How do we know that our Galaxy is surrounded
by dark matter? How much of the mass of
our Galaxy consists of dark matter, and what are some theories as to what the
dark matter is? Where is Sagittarius A*
(Sgr A*), what is it, and how do we know?
What
are the four types of galaxies in the Hubble classification system, and what
are their properties? Which of the four
types look reddish or bluish, and why?
What are the two largest galaxies in the Local Group? What sorts of processes take place when
galaxies “interact” (i.e.: collide or pass close to one another)? How do we know that there is dark matter in
galaxy clusters (cluster stability, gravitational lensing)?
What
are standard candles? How do
astronomers determine the distances to galaxies? What is the distance ladder?
What is the Hubble law, and what does it mean? How does one go about determining the value of the Hubble
constant, and why was this value uncertain?
How does the expansion of the universe differ from the explosion of a firecracker? How does one determine an estimate for the age of the universe using a galaxy’s distance and speed, and how is this related to the Hubble constant?