Physics & Astronomy 307 Autumn 2008 Homepage

Univ. Louisville

Instructor: Dr. Gerard Williger, NS 206, tel 852-0821
                   e-mail: williger@*
                   where *= physics.louisville.edu (please do not e-mail to my Groupwise acct)
                   My homepage is here
Office hours: after class (till 6pm) and by appointment;
I will not entertain questions on problem sets on the day they are due

Lectures: NS 312 and NS313, Mondays and Wednesdays 4:00-5:15pm
We'll use NS313 at the beginning but will use NS312 (across the hall, with a computer) for some lectures.

Text: Intro. Astronomy & Astrophysics, Zeilik  & Gregory, 4th ed., Brooks/Cole  (1998)

The course objective is to learn basic the basic physics of astronomical phenomena. A working knowledge of calculus and introductory college physics is assumed. Differential equations will help, but if you
have not had them, you can pick up what you will need.  The lectures will begin on Monday, Aug 20. 
Before the first lecture, students are expected to read the prelude as background, to be familiar with the terms
and concepts in it.  They are also expected to read Chapter 1.

A password-enabled protected site will contain answers to homework and midterm problems, if I do not
pass them out in class.  I may also put commentaries on common homework errors there as well.
Finally, all the PowerPoint files for my Astro 107 class from Spring 2008, plus animation files,
are on the protected site.  They're an excellent overview for the material in this course, and I
highly recommend your looking at the files.  We'll cover roughly chapters 1-15 from that course,
but not do too much on the planets.

Special dates on semester calendar for this class:
Thu 10 Sep **IN PLANETARIUM** (tentatively)
Thu 8 Oct midterm
*** Tue 10 Dec (Reading Day) final exam - *** 10:00am-12:30pm *** . (This is rescheduled from Sat Dec 13 at 1:45pm which everyone disliked!)

Here are  links for supplemental material and additional explanations

EXTRA CREDIT

1) Fri 19 Sep in NS112, 3pm (coffee at 2:30pm in Adams Room), attend Joe Meiring's seminar,
"Chemical Abundances in Low Redshift Quasar Absorption Line Systems",
and give a 200 word summary (typed, on paper) due on Mon 29 Sep (extended for Hurricane Ike).  It's worth a bonus of +2 points on your
homework score, after dropping the lowest one.  If you cannot attend, a substitute lecture is
"Cosmic Star Formation and the Metallicity History of Galaxies" by Lisa Kewley, on the STScI
talk archive for 2007 Feb 7.  Here is the link.  You must scroll down to her talk.  Write a 200 word
summary as above, due on the same date.   Note that this is a science talk, at a higher level than the
popular Bullitt Lecture, hence it's worth more extra credit.
Here is the PowerPoint file for it

2) Fri 26 Sep in NS112, 3pm (coffee at 2:30pm in Adams Room), attend Ralf-Juergen Dettmar's seminar,
"Gaseous Haloes of Spiral Galaxies and the Interstellar Disk-Halo Connection",
and give a 200-300 word summary (typed, on paper) due on Mon Oct 6.  It's worth a bonus of +2 points on your
homework score, after dropping the lowest one.  If you cannot attend, a substitute lecture is
"Gas in Galaxies: Puzzles and Prospects" by Leo Blitz, on the STScI
talk archive for 2007 May 2.  Here is the link.  You must scroll down to her talk.  Write a 200-300 word
summary as above, due on the same date.   Note that this is a science talk, at a higher level than the
popular Bullitt Lecture, hence it's worth more extra credit.


3)  Wed 29 Oct at 7pm in the planetarium, Bullitt Lecture by Caty Pilachowski
You can earn extra credit with the lecture. Attend the lecture and write a 250 word summary (typed, on paper).
It is due on Mon. 17 Nov (extended for a week due to the lack of the talk going online), and is worth a
bonus of 1 point to be added to the homework score after dropping the lowest one. 
Unfortunately, it has not been possible for the recording service to put the talk online.
Therefore, if you could not attend the lecture, you can watch one of these others.  The deadline is
the same: Mon. 17 Nov.
Here are your alternatives, from
the UL Astronomy talk archive. Descriptions of each lecture are on the talk archive website.

7th Bullitt Lecture, 2007 Oct 25, C. Robert O'Dell, Vanderbilt U,
Creating the Hubble Space Telescope

6th Bullitt Lecture, 2006 Apr 20, Alan Dressler, Observatories of the Carnegie Institute of Washington,
Galaxies, Stars, Planets, and Life: The Birth of the Modern Universe (caution: asx)

2007 Mar 26, Don Yeomans, NASA/Jet Propulsion Lab,
Killer Asteroids: Finding Them Before They Find Us

2006 Dec 1, Volker Beckmann, NASA/Goddard Space Flight Center,
The Violent Universe: NASA's High Energy Missions

2006 Sep 14, Chuck Keeton, Rutgers U,
Black Holes and the 5th Dimension (63 minutes; caution: asx)


Reading:
25-27 Aug: Prelude (for qualitative understanding), Chap 1-2
3 Sep: Appendix A10, Chap 3
      For a reference to time and celestial coordinates supporting Appendix 10, see this site from MSU
8-10 Sep: still Chap 3
15-17 Sep: Chap 4 and 7 (sections 7.5-7.6) (we'll skip Chapters 5 and 6)
22-24 Sep: Chap 8
29 Sep-1 Oct: still Chap 8
6 - 15 Oct: still Chap 8
20-22 Oct: Chap 10, 11
27-29 Oct: Chap 11, 12
3-5 Nov: Chap 12-13
10-12 Nov: Chap 13-14
17-19 Nov: Chap 15
24 Nov: Chap 16
1-3 Dec: Chap 17
8 Dec: Chap 19




Homework: due at beginning of class; answers in units given in the problem e.g. SI units OR standard
astronomical units (like AU or pc for distance, solar masses for mass, years for time etc.)
unless noted, following the format below.
Solutions will always be provided and you are responsible for all homework problems.
However, I reserve the right to grade only some of the problems,
those being graded to be announced when the homework is collected.
Problems are indicated as chapter.problem (e.g. 1.5 is chapter 1, problem 5).
YOU MUST SHOW YOUR WORK (INCLUDING ORIGINS OF ALL NUMBERS) SO THAT I CAN
FOLLOW YOUR CALCULATIONS AND GIVE PARTIAL CREDIT.
HW01, due Wed 3 Sep: 1.5* (for Pluto, not Mercury), 1.7, 1.13, 2.3*, 2.4* (take Jupiter's "surface" to be its cloud tops)
STATS: 9 done, mean=1.98/4, std dev=1.30/4, range=0.7-4.0, COMMENTS ON HW01
HW02, due Wed 10 Sep: 2.11 (also do for Mercury), 2.13*,
3.2* (give azimuths like NNE, ESE, WSW etc.; give maximum solar
altitude and minimum solar zenith distance in degrees, and insolation relative to June 21), 3.5*, 3.7
For 3.2, make a table like this:
                         rise azimuth   set azimuth   Sun-horizon angle   noon altitude   noon zenith distance   insolation/insolation(June 21)
Mar 21, lat 0
Jun 21, lat 0
Sep 21, lat 0
Dec 21, lat 0
repeat for lat=35, 90 degrees
STATS: 8 done, mean=2.10/4, std dev=1.07/4, range=0.6-3.5, COMMENTS ON HW02
HW03, EXTENDED TO MON 22 SEP (originally due Wed 17 Sep): 3.3*, 3.11*, 4.4*, 4.10, 4.15
Hint on 4.10: Note that if vrms/vesc = 1, 0.25, 0.20, <0.10 then the expected lifetimes
are a few years, several thousand years, a few hundred Myr and a few Gyr respectively.
STATS: 8 done, mean=2.23/4, std dev=1.08/4, range=0.9-3.6, COMMENTS ON HW03
HW04, due Mon 29 Sep: 4.7*, 4.8, 4.14, 7.1*, 7.6*
STATS: 8 done, mean=2.80/4, std dev=0.53/4, range=2.2-3.7, COMMENTS ON HW04
HW05, due Mon 6 Oct: 8.4,8.9,8.10*,8.16*, (statistical weights g_n=1 = 2, g_n=2 = 8),
8.18* (A'=9.4x10⁵⁵ kg^3/2 J^-3 s^-3, g₊/g₀=2, and A=A'(g₊/g₀))
STATS: 5 done, mean=2.96/4, std dev=0.42/4, range=2.6-3.5, COMMENTS ON HW05
HW06, due Mon 20 Oct: 8.8*, 8.12 (hint: use Taylor series as needed), 8.13*,
8.17* (A'=9.4x10⁵⁵ kg^3/2 J^-3 s^-3, g₊/g₀=1, and A=A'(g₊/g₀)), 8.19; not for HW but know how to do 8.11 (easy)
STATS: 4 done, mean=3.10/4, std dev=0.22/4, range=2.9-3.4, COMMENTS ON HW06
HW07, due Mon 27 Oct: 10.1,10.3*,10.7,10.10*,10.17*
STATS: 4 done, mean=2.83/4, std dev=0.34/4, range=2.4-3.1, COMMENTS ON HW07
HW08, due Mon 3 Nov: 11.8 (show work),11.10 (also: what would be apparent mag at distance 10~kpc?),
11.20* (do for 45 deg, not 30 deg), Color Problem*, 12.4*
Color Problem:
(a) Compute the Planck function in wavelength for 4400A, 5500A, 6200A, 7700A
for temperatures 3000K, 5000K, 10000K, 20000K.  The wavelengths correspond to
the centroids of the B,V,R,I filters respectively, and the temperatures correspond
roughly to M, G, A and B stars.  Using the Planck curves as fluxes (dlambda=1A is fine), compute
the colors in terms of magnitude B-V and R-I in temperature. 
(b) Why do astronomers tend to use B-V as a main reference for colors of spectral types rather than R-I?
STATS: 4 done, mean=2.40/4, std dev=0.41/4, range=2.1-3.0, COMMENTS ON HW08
HW09, due Mon 10 Nov: 12.6*, 12.7, 13.5*, 13.12, A (radial velocity pblm)*:
Radial Velocity Problem:
(A) see radial velocity calculator on class links page for Chap. 12
Use 5 system parameters:
1) mass ratio
2) semi-major axis a
3) eccentricity e
4) inclination i
5) angle to line of apsides w
Observe these characteristics of light curve:
a) maximum radial velocity v_r
b) ratio of v_{r,1}/v_{r,2}
c) period P
d) FWHM of maximum, minimum v_r for a given star
e) symmetry of v_r curve at maximum, minimum v_r for a given star
f) time from v_{r,max} to v_{r,min} compared to v_{r,min} to v_{r,max} for a given star
g) does v_{r,max}=-v_{r,min} for a given star?
How does each system parameter affect each observable? Some system parameters will affect more observables than others. Make 7x5 grid for presentation. Be sure to test the elliptical case (e>0) as well as the circular case (e=0) when you can!
STATS: 4 done, mean=2.83/4, std dev=0.33/4, range=2.4-3.2, COMMENTS ON HW09
HW10, due Mon 17 Nov: 13.14 (use Figs. 13-7, 13-8, 13-9, 13-10),
13.17* (note: MgI is [accidentally?] not shown in Fig 13-6; do your best to
explain why Fig. 13-6 does not act as you think), 14.6*,14.14*,14.15
STATS: 4 done, mean=3.13/4, std dev=0.39/4, range=2.7-3.5, COMMENTS ON HW10
HW11, due Mon 24 Nov: 15.7,15.11*,15.14*,15.15*,15.20
STATS: 4 done, mean=3.15/4, std dev=0.42/4, range=2.6-3.6, COMMENTS ON HW11
HW12, due Mon 1 Dec: 16.6 (use core mass of 0.1Mstar, L=M^3.3, lifetime = M/L = M^(-2.3)), 16.8,16.10*,
A (2-point reading assignment): read the paper http://arxiv.org/abs/astro-ph/0605088
(You MUST be able to download the paper WITHOUT going through any subscription/library rigamarole --
and you SHOULD practice getting papers off archives.  If you CAN'T download the paper, here is a pdf
version -- but in that case, please TELL ME so we can figure out the problem you're having accessing arXiv.org)
Then answer these questions:
*A) What most likely formed HI holes in other galaxies? What mechanisms appear unlikely?
*B) Explain the post-T-Tauri problem and the current questions we have about it.
You are particularly encouraged to work together on the reading assignment.
For some astronomical terms, see
http://nedwww.ipac.caltech.edu/level5/Glossary/frames.html
If a term is not in the astronomical glossary, ask each other and ask me.
I do not expect you to understand 100% of the paper. But, I do expect you
to get the general idea.
STATS: 4 done, mean=3.80/4, std dev=0.23/4, range=3.6-4.0, COMMENTS ON HW12
HW13, due Mon 8 Dec: 16.7 (use R propto M^0.6 as in Fig 12-11A), 17.3 (use virial theorem,
classical KE for v=c, assume matter is ionized H), 17.7 (assume WD has M=0.7Msun, R=0.01Rsun,
note R propto M^(-1/3)), 17.11, 17.15

* means the question is major, graded with a weight of 1 point, of which there are three.
Other questions (typically two) will be graded with a weight of 0.5 points.
Leaving a question blank gets no credit, ever.


The class mid-term will be on 8 Oct. It will be closed book with a formula sheet which I provide.
No other aids (paper or electronic) are allowed, except that calculators will be needed.
I will have grades available by the time to drop if you want.  (But, since only ~33% of the
grade will be determined by that point, you can ALWAYS redeem yourself on the final! 
I encourage you to see me before you drop the class.)
Midterm STATS: 4 taken, mean=29.6/74, stddev=20.6/74, range=11.5-51.0, data=11.5,12.5,43.5,51.0
GRADES THROUGH HW5 (DROPPING THE LOWEST), MIDTERM:
grade = [(homework average/4)+midterm/74+0.2*participation/10]/2.2 (extra credit not added in yet)
Participation is only included at the 5% level since we only are dealing with the homework and
midterm, so we don't want to over-weight it with respect to the other parts of the class in
the middle of the semester.
mean = 55.4%, stddev=23.0%, data=30.7,41.7,69.2,79.8%
Please note that this class is massively curved! If you want more details, please talk to Dr. W.

The participation grades are subjective and are subject
to change.  Generally, if you come to class and ask an
average number of questions, you'll get a 7 out of 10.
If you just sit there, you'll get around a 5.  If you skip class
(which I can note in any way, including not
picking up homework) then you can get <5.  I also am less
likely to be generous with participation if you habitually don't
turn in homework, since doing homework generates questions
and feedback on common misconceptions.



FINAL EXAM officially scheduled for Sat, Dec 13, 1:45-4:15pm  - CLOSED BOOK. I will give an equation sheet and needed constants.
Given that the official exam time is on a Saturday, I will discuss moving it with the class to Reading Day,
the last day of class or another mutually acceptable day. If we cannot agree on a time, I may move it
to the last day of class. I will announce this by the first class day after the latest day to drop without petition.

GRADING:
Your grades are composed of 4 parts: homework avg, midterm, final, participation.
All four parts are required for completing the course.
The lowest homework grade is dropped.
Your grade is: 0.25*HW+0.25*MIDTERM+0.40*FINAL+0.10*PARTICIPATION


Partial Credit:
Homework and tests will have partial credit available.  You MUST show
your work, in particular the equations which are used to begin a
calculation, to get any credit at all.  You must  keep track of significant
digits.  If the least accurate number going into a calculation has n
significant digits, then the answer should have that number, also.
If you happen to do the wrong homework problem instead of an assigned
one, you will typically not get credit for it.

Scientists need to check their own work.  To this end,
you are expected to have an idea what a reasonable answer is, even though
you might not get the correct answer.
     A reasonable answer has the correct units -- use dimensional analysis!
It also has an order of magnitude
which is not wildly inconsistent with information given in the problem or common
knowledge.  For example, calculating a core temperature of the Sun to
be 3K is a nonsense (unreasonable) answer, because its surface and even
Earth are much hotter than that.  If your answer is way off
and you note it and attempt to explain where the problem might be,
I will take it into consideration.
     If you give a nonsense answer due to simple arithmetic or mathematical
errors and do not catch it, you may not get partial credit for setting up the
problem correctly.



Planned Syllabus (subject to modification; links for supplemental material are provided): 

Here are also links (from an Astronomy 107 links site) for recent discoveries,
(simple) equations used in that class and supplemental material.

Here is a list of errata for Zeilik & Gregory.

Topics covered:
Chap 1, Celestial Mechanics
Chap 2, The Solar System in Perspective
Appendix 10, The Celestial Sphere
Chap 3, Dynamics of the Earth
Chap 4, The Earth-Moon System
Sec. 7.5-6, Interplanetary Gas & Dust and Gravitational Impact Parameter
Chap 8, Electromagnetic Radiation and Matter
Chap 10, The Sun: A Model Star
Chap 11, Stars: Distances and Magnitudes
Chap 12, Stars: Binary Systems
Chap 13, Stars: The Hertzsprung-Russell Diagram
Chap 14, Our Galaxy: A Preview
Chap 15, The Interstellar Medium and Star Birth
Chap 16, The Evolution of Stars
Chap 17, The Deaths of Stars
Chap 19, Galactic Rotation: Stellar Motions

Additional material from other chapters and books will be added as needed.

There will be graded homework (25%), one midterm (25%) and one final examination (40%).
If you miss the midterm and you give me a week's
advance notice with a documentable reason,  the make-up will be a one hour
oral exam.  For the final, it's up to a two hour oral.
General test policy is that once you leave the room, you can't come back in.
The worst homework grade will be dropped.
You are permitted to help each other in groups, but you must turn in your own work.
A subjective score for class participation (including improvement)
will also count for 10% of the grade.   Grading will be done on a curve.
There is no fixed percentile for grades, nor any absolute standard for letter
grades. The plus-minus grading system (A, A-, B+ etc.) will be used.