Physics & Astronomy 590 Spring 2024 Homepage

Univ. Louisville

Instructor: Dr. Gerard Williger, NS 206, tel 852-0821
                   e-mail: gmwill06@*
                   where *= louisville.edu (please do not e-mail to my Groupwise acct)
                   My homepage is here
Office hours:  by appointment;
*I will not entertain questions on problem sets on the day they are due*

Lectures: Mon/Wed, 11:55am-1:10pm, Nat Sci 313, 2 x 1.25 hours/week

Text: Foundations of Astrophysics, Ryden  & Peterson, 1st ed., Addison-Wesley  (2010)

The course objective is to learn basic the basic physics of astronomical phenomena. A mastery of calculus
and introductory (calculus-based) college physics is assumed, plus the material for Astronomy 307.
Differential equations will help, but if you
have not had them, you can pick up what you will need.  The lectures will begin on Tuesday, Jan. 11.

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 a recent Astro 107 class, 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 try to cover roughly chapters 13-24 in our textbook.

GRAPHING CALCULATORS ARE BANNED ON TESTS.





UL Student Support Page for the COVID-19 situation.
 

Here are  links for supplemental material and additional explanations
astro-news for Astro 107 (see for solar plasma ejection article etc.)



Reading/Schedule:

Week 01: Jan 08-10 (guest lecturer: Dr. James Lauroesch while I'm at the AAS Meeting in New Orleans)
Week 02: Jan 17 (ML King Day Jan 15)
Week 03: Jan 22-24
Week 04: Jan 29-31
Week 05: Feb 05-07
Week 06: Feb 12-14
Week 07: Feb 19-21
Week 08: Feb 26-28
Week 09: Mar 04-06
Week 10: Mar 18-20
Week 11: Mar 25-27
Week 12: Apr 01-03
Week 13: Apr 10 ; also 11 (6-7:15pm) - note Great North American Eclipse Apr 8 - NO CLASS THAT DAY
Week 14: Apr 15-17
Week 15: Apr 22


Midterm, Quizzes and Mini-quizzes:  tentative so far.
Board Problems in teams of 2 may be substituted for mini-quizzes.

Week 01: Chap 13; +  Astro-107 Ch11 slides
Week 02: Chap 13
Week 03: Chap 14-15 + Astro-107 Ch12 slides + MQ111
Week 04: Chap15
Week 05: Chap 15-16 + Quiz 1
Week 06: Chap 16-17
Week 07: Chap 17 + Astro-107 Ch13-14 slides + MQ2
Week 08: Chap 18
Week 09: Chap 18-19 + Astro-107 Ch15 slides + MIDTERM, Mar. 4 (confirmed, due to Dr. W's surgery)
11-15 Mar: SPRING BREAK
Week 10: Chap 19-20 + Astro-107 Ch16-17 slides
Week 11: Chap 20 + MQ3
Week 12: Chap 21-22 (Quiz 2, Apr 6); + Quiz 2
Week 13: Chap 22-23 + Astro-107 Ch18 slides
Week 14: Chap 23-24 + Astro-107 Ch19 slides + MQ4
Week 15: Chap 24 + Astro-107 Ch19 slides

READING DAY: Tue Apr 23, 2024
TBD: question session for final
Tue Apr 30, 11:30am-2pm: Cumulative FINAL EXAM, can be changed by CLASS VOTE
Tue or Wed, Apr 30-May 1, 2024, time TBD: Class Presentations, in person, to be determined by CLASS VOTE

Presentations should be about 10 minutes talking, 2 minutes of questions each, unless class agrees to longer times




CHAPTER TOPICS:
13 - magnitudes, stellar luminosities/sizes, binaries, radial velocity/light curves
14 - stellar atmospheres, Hertzsprung-Russell diagram
15 - stellar interiors, equations of stellar structure
16 - interstellar medium, H II regions
17 - star formation, evolution of solar mass stars, Cepheids/RR Lyrae stars
18 - white dwarfs, neutron stars, stellar mass black holes, supernova remnants
19 - Galactic morphology, structure, rotation curve, nucleus
20 - galaxy classification, spectra, supermassive black holes, Hubble-Lemaître law
21 - active galaxies, accretion disks, quasars, intergalactic medium
22 - galaxy clusters/superclusters, galaxy mergers
23 - cosmology (Newtonian and Einsteinian), spacetime metrics, Friedmann equation
24 - accelerating Universe, cosmic microwave background, Big Bang, consensus model

CHALLENGE PROBLEMS: Done for learning. The ~60-70 problems total to 1% of the grade.  Learn them for tests.
COUNTS PROBLEMS -- TO BE TURNED IN: These are graded homework.  You can work together, but must turn in your
own, original solutions. 

YOU MUST SHOW YOUR WORK (INCLUDING ORIGINS OF ALL NUMBERS) SO THAT I CAN
FOLLOW YOUR CALCULATIONS
AND GIVE PARTIAL CREDIT.
PLEASE STAPLE ANY WRITTEN HOMEWORK! LOOSE PAGES MAY BE LOST.


HOMEWORK ASSIGNMENTS


Challenge problems are for practice and will be similar to some test problems. They are for learning/exercises, and to be turned in for participation credit. Ask for help if you need it to learn how to do them.

CHALLENGE PROBLEMS
Note: If you need to look up a parameter, use the text (or tables in the back) of Ryden & Peterson FIRST.
Wherever you find parameters, please give your source e.g. for distances, absolute magnitudes, colors etc.

HW01 due Wed 17 Jan: 13.1, 13.2, 13.3, 13.4, 13.5, 13.6 (use material from 307 or ask if you need help)
HW02, due Mon 22 Jan: 13.7, 13.8, 13.9, 14.2 (use Ch. 5 information/equations)
HW03, due Mon 29 Jan: 14.1, 14.3, 14.5, 14.7 (hint: use bolometric magnitudes), 15.5 (see Astro 307 notes),
HW04, due Mon 05 Feb: 14.4, 15.3, 15.6, 15.7, 15.8, 15.9 (in low-mass MAIN sequence stars...)
      plus Counts Scales-a (0.25% credit)
HW05, due Mon 12 Feb: 16.1, 16.3, 16.4 (use Astro 307), 16.7, 16.10 (assume solar spectrum means photosphere)
HW06, due Mon 19 Feb: 16.2, 16.6, 16.8, 16.9, 17.1, 17.6 (look up n,T in book or notes)
HW07, due Mon 26 Feb: 17.2, 17.3, 17.4, 17.5, 18.1, 18.5 (use solar wind physics from Astro 307)
HW08, due Mon 18 Mar (delayed from 6 Mar for Midterm move): 18.2, 18.3, 18.4, 18.6, 18.7 (hint: use eqns of state for degen, non-degen gas, equate pressures; also put a point for the solar core)
HW09, due Mon 18 Mar: 19.2, 19.10 (use Astro 307 material, know there is a supermassive black hole in the Gal. Center with M=3.7 million Msun; look up B1V star in text appendices)
HW10, due Wed 27 Mar: 19.1, 19.3, 19.5, 19.6, 19.9, 20.1
HW11, due Mon 01 Apr: 20.2, 20.4, 20.6, 20.7, 20.8, 21.1, 21.2
HW12, due Wed 10 Apr: 21.3, 21.6, 21.7, 21.9, 22.1, 22.2
HW13, due Mon 15 Apr: 22.3, 22.4, 22.5 (assume n*=1/pc^3, R*=0.5 Rsun, N=2e11 stars, each galaxy is a cube), 22.6, 23.5
HW14, due Mon 22 Apr: 23.1, 23.2, 23.4, 24.1, 24.3, 24.4

COUNTS PROBLEMS/EXTRA CREDIT
Any paper or seminar/talk write-ups should be typed, on paper. Please use TWELVE POINT TYPE (not smaller).
Grammar/spelling/style count. CITE any outside sources you use (papers, websites etc.)
Reading beyond the textbook and notes is encouraged! It's good to learn how to look up information.
Keep a backup for yourself.  Do about 300 words (1 page) unless otherwise noted. Definitions do NOT count against the word total.
 
IN GENERAL for paper summaries,
0) Look up and list any definitions you need to learn. If you need help, ask.
i) your first sentence should be a punchy summary: "This paper shows/discusses ..."
Then clearly identify at least these points:
ii) the main science question(s) or paper goal(s) in the context of a brief background description e.g. "why is this investigation being done"
iii) data source description (e.g. telescopes, surveys etc. if it is an observational paper) or whether the paper is theoretical; not needed for a review paper
iv) methods and error analysis (unless it's a review paper)
v) results, discussion/conclusions
vi) future work/implications
vii) whenever possible, be quantitative and specific, rather than general and/or vague
viii) at the beginning of the paper, emphasize in one sentence what is NEW and DIFFERENT in this paper compared to other work in the field
IMPORTANT: ***Avoid copying phrases or sentences verbatim.*** Put the material into your own words. Use plural with "data", and singular with "datum". Do not use constructions like "The article says", but rather give the author's last name (if a single author paper), the two authors' surnames (if a two author paper) or the first author's last name + "et al." for >=3 authors.


COUNTS-SCALES PROBLEMS
Each of these counts as 0.25% of the grade:

Scales-a: Magnitudes.  Draw a logarithmic chart showing apparent magnitude from -26 (the sun) to +30 (Hubble Deep Field).
I recommend hand-drawing it to learn it better, but if you really prefer to do it on a computer, you can. 
Look up and put on it typical apparent (not absolute) values for the full moon,
8 major planets, Pluto, Eris, Arrakoth/Ultima Thule, an M0V main sequence star at d=10pc and at d=1000 pc,
Vega, Sirius, Polaris, Mira at maximum, Mira at minimum, 3 Messier objects (pick any you like),
the depth of the Sloan Digital Sky Survey, a sun-like star (M_V=+5) at these distances: 
100, 1000, 1e4, 1e5, 1e6 pc (parsecs) and a B0V star at 10 pc and at 10,000,000 pc.  Label your plot well. Due on Mon 5 Feb.

COUNTS 1: Summarize Bessell 2005, ARAA, 43, 293, "Standard Photometric Systems", on the class protected site (Articles subdirectory). 
It's long so I just want parts of it: Beginning/Sec 1-2.3, 5.1-5.3, 6-8. (By the way, Robert F. Wing was my teacher for the equivalent of Astro 308.) 
This paper is long, so for this summary write a maximum of about 500-600 words (2 pages).

The goal is to learn about the various filter systems, so give details about each for the given sections and compare them.
Note that it is a data/tools paper, so it does not have the traditional science question, data,
methods sections etc.  Just summarize it and cover the main points. NB: broadband has width dlambda > 400-1000 A, not < 1000 A.
It's a misprint in the paper. See broadband filter widths in Table 1.
Due Wed 24 Jan, 2024 at the beginning of class.


COUNTS-2:  Color Problem: Compute the Planck function in
wavelength for 4400A, 5500A, 6200A, 7700A for temperatures 3200K,
5800K, 11000K, 25000K.  Also do Vega (T=9600K). 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.   Make a plot of flux vs. wavelength for each temperature.
RESPECT RULES FOR SIGNIFICANT FIGURES.
**Remember that Vega's spectrum DEFINES all magnitudes for each band as zero and thus all colors as zero.**
Why do astronomers tend to use B-V as a main reference for colors
of spectral types rather than R-I? Due Mon 5 Feb at the beginning of class.


COUNTS-3: Stellar Spectral Classification Problem - **IN PAIRS** Group 1 = CS & EP ;   Group 2 = TB & BS
Identify the spectral classes and subclasses for the spectra given out on paper the other week.
1) Due on Mon 19 Feb at the beginning of class
2) Identify the stars by spectral class and subclass. Do not spend much time to determine the luminosity class (I-V), as that is more difficult.
(Most are V, though not all.  You can try if you like, based on line widths, though it is not required.)
3) Give all the identifying reasons you can (all spectral indicators covered in class or wherever else you can find them). Explain your reasoning fully.
Include a **labelled version** of the spectrum, identifying as many lines as you can.
Note which sorts of lines go together based on the figures in the lecture notes.
4) Give sources for any material you use beyond the book or lecture.
5) Remember that you only have the optical portion of the spectra.
6)  Give justification for your classifications, in terms of narrow lines, broad lines, flux peak, slope, "raggedness" (in reality weak lines), continuum flux at 3200-3500A relative to peak flux or any other features you see. ANNOTATE each spectrum with line identifications to be clear.  
See a sample, annotated ground-based solar spectrum (with telluric (Earth's atmosphere) plus Fraunhofer names for lines) here
Common lines (in Angstroms) are:
TiO bands in the red (sometimes very broad), including 4584, 4626, 4761, 4810, 4847, 4954, 6650-6850 (v broad), 7050-7150, 8432, 8683A
H-alpha  6563
NaI doublet at 5896 (may not be resolved)
HeI 5876
HeII 5411
FeI 5270 (solar spectrum)
H-beta   4863
C2 4670 (broad, shallow; see Swan Bands)
HeI 4471
H-gamma  4342
CaI & FeI (blend), 4308 /4309 (Fraunhofer "G" lines, strong in sun=G2V star)
CaI 4226
H-delta  4103
FeI 4045
CaII H,K doublet lines at 3935,3970
H-epsilon 3970 (calculate higher order lines yourself or look them up, as needed - they sometimes are visible)
HeI 3965
FeI 3820 (Fraunhofer "L" line, strong in Sun=G2V star)
MgI 3835
FeI 3730
Balmer break 3646

You can find more information at http://skyserver.sdss.org/dr1/en/proj/advanced/spectraltypes/lines.asp#spectab
You can find a GREAT online tool via the WKU Astro 106 online spectral calculator
Another resource: Columbia U solar spectral exercise (includes description of A-K lines from 19th century)
Also, see the paper by Kesseli et al. (2017, ApJS, 230, 16) on the class protected site under "Articles" or on ADS.

You are free to look up any other stellar spectral catalogue, list of lines etc.
CITE YOUR REFERENCES.


COUNTS-4: Radial Velocity Problem
Use the Python program Orbit3.py on the class protected site (under the "Programs" subdirectory).
Download the Excel template there or use the copy on BlackBoard.
Vary each of the input parameters (top row of Excel file) and note how the observable parameters
change (first column).  In detail:
EXPLORE PARAMETER SPACE TO FIND OUT HOW RADIAL VELOCITY VARIES WITH VARIOUS PARAMETERS.
TEST OUT A GRID OF VALUES FOR EACH PARAMETER.
VARY THE PARAMETERS ONE BY ONE, SYSTEMATICALLY FROM LOW TO HIGH OB VALUES.
 START WITH THE DEFAULT VALUES AND EXPLORE THE POSSIBILITIES. 
THEN, REPORT ON THE EFFECTS ON THE RADIAL VELOCITY CURVE.
Use 5 system parameters:
1) mass ratio (default: 1:1) - while keeping TOTAL MASS the same at all times
2) semi-major axis a (default: 1 AU)
3) eccentricity e (default: e=0)
4) inclination i (default: i=90 deg)
5) angle to line of apsides w (default: w=0)
Observe these characteristics of radial velocity curve, and describe **how** they change WITH THE VARIATION OF EACH INPUT PARAMETER.
a) How does the maximum radial velocity v_r
vary with your input parameters?
b)
How does ratio of v_{r,1}/v_{r,2} vary with your input parameters?
c) How does the period P vary with your input parameters?
d) What are the RELATIVE FWHM (to period) of maximum vs. minimum v_r (as a function of time and as a fraction of total period) for a given star?  FWHM_vrmax/P vs FWHM_vrmin/P
If you do not know the concept of FWHM well, ask me.
e) Consider and describe the symmetry of v_r curve at maximum (for v_r>0); then consider/describe separately the symmetry around minimum v_r (for v_r<0) for a given star.
f) What is the time from v_{r,max} to v_{r,min} compared to the time from v_{r,min} to v_{r,max} for a given star?
g) How does v_{r,max} change with respect to v_{r,min} for a given variable and given star?
How does each system parameter affect each observable? Some system parameters will affect more observables than others.   Examine the radial velocity curves in a "grid", varying the parameters
systematically.  Put answers into the Excel file.
Be sure to test the elliptical case (e>0) as well as the circular case (e=0) whenever you can!
Due: Wed Mar 6, 2024, to be turned in via BlackBoard.  This is a TEAM assignment, as I understand that
NOT all students can run the software.
You can consult with each other on it as speaking with each other may aid your learning.
However, write up your results, one write-up per team, and include as much detail as you can.  You should include some
illustrative screenshots as you see appropriate to explain your conclusions (bonus possible).

ASK QUESTIONS IF YOU NEED CLARIFICATION.


COUNTS-5: Color-Magnitude Diagram Problem

This is worth 2% on the grade.
Go to the class protected site and look in the Counts4 subdirectory.  Download two files:
File-1: tab_cl01_index_bvri.xlsx - a table of apparent (not absolute!) BVRI magnitudes for a star cluster
File-2: pecaut13apjs208.9_bvri_tab5_mainseqcolors_excel.xlsx - a table of main sequence colors and temperatures from Pecaut & Mamajek (2013),
ApJ Supp, 208, 9
In addition to these use Table A.5 in Ryden & Peterson, which has a list of absolute V-magnitudes for main sequence stars, though
in a less detailed grid (but sufficient for our purposes).
Due on Mon Apr 22 at the beginning of class. No extensions!
1) Plot up color-magnitude (C-M) diagrams for the stars in File-1.  Caution:  not all stars are detected in all bands.
Non-detections are indicated by the "flag" value of 99.999.  Do not consider those magnitudes.
Use V as the reference magnitude. Try these colors: B-V, V-R, R-I, V-I
Label your C-M diagrams and axes clearly.
Remember that many stars (about 30-40%!) have no B magnitudes, because they are below the magnitude limit of the observations.
Some also have no I magnitudes, though the fraction is small.
So, there will be significantly fewer stars in B-V (x-axis) vs V (y-axis) compared to other C-M diagrams.  
Plot from hot to cool as left to right on the x-axis, and  faint to bright as low to high on the y-axis.  This mimics the H-R diagram.
If you need help with plotting, ask your classmates.  If they cannot help, then ask the instructor.
2) Compare the various colors for the C-M diagrams.  Which one(s) are most useful to determine the main sequence turn-off and why?  Specifically:
i) Give the main sequence cutoff in B-V and V, with errors in B-V and in V, using that plot.
ii) Give the main sequence cutoff in V-R and V, with errors, using that plot.
iii) Give the main sequence cutoff in V-I and V, with errors, using that plot.
Your answers may be different for each color

3a) Assume no reddening.  Which spectral type and effective temperature T_eff are best indicative of the main sequence turn-off
FOR EACH COLOR: B-V, V-R, V-I.
     Do they vary depending on the color you pick?  What is the corresponding or equivalent B-V color of your turn-off and its uncertainty?  (You'll have to look up the V-R, R-I, V-I colors in the tables and find the corresponding B-V for each.)
    What is your uncertainty in spectral type and T_eff for each of the colors?  (We use (B-V) as a "reference" color, but note that it may not be the best color with these data to determine
    the main-sequence turn-off.)
3b) Now assume a color excess of E(B-V)=0.25. What is the corresponding main sequence turn-off and
  spectral type and T_eff, with upper and lower bounds?  How does the effect of adding a
color excess compare to the equivalent (B-V) uncertainty in (4a)?
4) For the main sequence turn-offs and uncertainties in 4a-b, look up and list the corresponding absolute magnitudes M_V in Table A.5, with upper and lower bounds.
Interpolate as necessary.
5a) Assume no reddening.   What is the distance to the cluster in pc and uncertainty (upper and lower bounds)?
5b) Now assume 0.25 mag of E(B-V).  Calculate the extinction A_V (using the empirical value for R) and use it with a distance estimate.  Now what is the distance to the cluster in pc, with upper and lower bounds?
6) Again consider your main sequence turnoff spectral type and T_eff, with and without a color excess. 
Consult the mass-age-main sequence lifetime table from the Australia Telescope National Facility site
Logarithmically interpolate to get the age associated with your T_eff for your main sequence turn-off,
since the mass-age relation is a piecewise power law.  How old is the cluster in Gyr without reddening?  with reddening? 
What is your uncertainty without reddening?  with reddening?
What are your overall conclusions about the age of the cluster and the presence of any reddening?

Ask for help from the instructor if you need it.  Ask questions if something is ambiguous or confusing.


Grading in a nutshell:
quizzes and tests: 80% of grade; midterm counts 5/8 of final exam, quizzes (4-5%)/mini-quizzes(~1%) make up rest
presentation of a refereed journal article: 7%
participation: 5%
graded homework: 8%

GRADE STATS:
Mini-Quiz 1: 3 taken, mean,std dev = 6.2/10+-3.4, high 10.0
Mini-Quiz 2: 4 taken, mean,std dev = 2.8/10+-3.0, high 7.2
Mini-Quiz 3: 4 taken, mean,std dev = 5.3/10+-3.3, high 10.0
Quiz 1: 4 taken, mean,std dev = 8.8/10+-1.6, high 11.0
Quiz 2: 3 taken, mean,std dev = 5.9/10+-3.6, high 10.0
Midterm: 4 taken, mean,std dev = 24.0/50+-12.2, high 37.6


EXTRA CREDIT:


1) TBA

PRESENTATIONS:
Here are the rules.
0) Pick a paper you can understand *backward and forward*.  If there are terms, concepts, parameters etc. you do not understand,
I expect you to learn and explain them to the rest of the class (and to me), in your write-up, slides and presentation. 
If there are too many such terms/concepts/parameters for you to do this, do not pick such a paper.  It's MUCH better to do a *great* job
on a simple paper than a so-so job (at best) on an extremely complicated one.
1) topics+proposed papers due Thu 10 Mar (before Spring Break)
2) maximum 10 minutes+2 minutes questions, strictly enforced, SLIDES DUE (POWERPOINT OR PDF) TBA
3) I recommend about 7-10 slides
4) explain a-the scientific question, b-background, c-the methods/data, d-what is new (the discovery/result), e-the meaning for the big picture/science and future work
5) Your audience is your classmates. They should understand what you do. If they don't, you haven't done your job to explain it to them.
6) You're encouraged to get graphics from other articles, Wikipedia etc. BUT CITE your sources!
7) FORBIDDEN topics: General relativity, anything related to GR (such as complex calculations with neutron stars or black holes), "strange" stars or other quantum mechanics not covered in class, or any other subject which is not covered in our textbook.  GR is not a prerequisite
for our class, and most people have not (yet) taken it, though I recommend it for future studies.
8) Use a REFEREED journal article, 4-6 pages maximum, on any subject in Astro 307 or 590. The more recent the article is, the better. A hard limit is a maximum age of five years. You are encouraged to read other papers for background material, and these can be longer, but your primary one should be short. Review papers on anything (as they tend to be long and not have a science question), general relativity, modified gravity, quantum gravity and nuclear physics we haven't covered (e.g. quarks) in particular are NOT allowed.  The standard journal search engine is
ADS.  I will introduce its use to you if you need it.
8) There is a STRICT upper size limit of 6 pages (4-5 pages preferred) in any journal. No exceptions. Remember, these talks are SHORT.
9) I recommend getting an article from the following. Try especially the Letters from each journal.
Nature
Astrophysical Journal
Astrophysical Journal Letters
Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society - Letters
Astronomical Journal
Astronomy & Astrophysics (especially Letters)
Publications of the Astronomical Society of the Pacific
Icarus (solar system journal)
Publications of the Astronomical Society of Japan
If you wish to present a paper summary from another journal, please clear it in advance with G. Williger.
Other refereed journals are available via the NASA ADS site, and
arXiv preprint server (look for PASJ articles or other hard to find articles here) site.

10) WRITEUP:
You will also need to write an approximately 600 word/two page summary of your paper, which is worth 1/3 of the
presentation grade (more than a regular paper summary).
Write in good scientific prose:
a) science question
b) observations/data sample (if observational) or methods (if theoretical)
c) results
d) conclusions
e) further work
This is due typed, on paper, when you make your presentation.  You may include background material from other papers.
Cite liberally.

GOOD PRACTICE FOR SLIDES:
Use variable colors, font size, boldface, underlining, italics etc. Avoid monotony. **MAKE FONT SIZE BIG for those in the back of the room.
No more than 1 slide per minute.
Each slide should have a title of one to a few words - keep reminding the audience what's going on and guide step by step.
Use background boxes, indentations, bullets etc. Avoid unbroken blocks of text.
Use "telegraph language", minimizing words. Do not write many complete sentences. Speak them instead.
Have at least one graphic per slide, even a small one.
A little humor can be helpful, but keep it restrained so it does not dominate your message; use like salt and pepper in a recipe.
Put references on the slides where they are used (just author and year). Do not make a slide for references.
Your LAST slide should be "conclusions and further work". It will start the discussion after your talk.
**Anticipate one to a few questions and have slides as "extra material" in case you need them.
WHEN TALKING:
Do not read your slides.
Modulate your voice pitch and speed. Speak with expression. Do not be monotone. Do not speak too fast.
*MAKE EYE CONTACT WITH YOUR AUDIENCE FREQUENTLY.*
Avoid saying "um". It distracts your audience from your message.
*PRACTICE* your talk so it's smooth. Have your friends/classmates critique you.
Know your material very well and anticipate some potential questions. Have a slide or two ready after the end of your talk
in case someone asks the question you think will come under "Extra Material".
Keep to your time limit (~10 minutes). You should practice your talk at least 3 times with it successfully within your time limit.
Ideally, you should not need notes. But, use them if you must.




Participation grades  are subjective and are subject
to change.  They result from a combination of class participation (comments and
questions) plus performance at any problems done at the board in class, or assisting other
students doing so.  
If you never say anything or skip class (which I can note in any way,
including not 
picking up homework) then you can get as little as zero.  I also am less
likely to be generous with participation if you habitually don't
turn in any written, assigned homework, since doing homework generates questions
and feedback on common misconceptions.

GRADING:
Grades are composed of
tests 80%: 1 cumulative final, 1 midterm, 2-4 quizzes; also 0-9 miniquizzes (1% each), possibly questions at the board
presentation 7%
homework + participation 13%
Details are on the syllabus.


The presentation will involve summarizing a paper from the literature.


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. Leaving a question blank definitely earns a zero. 
On homework, I also count it as a sign of lack of participation.


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.


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

Planned material to cover (subject to modification; links for supplemental material are provided):
orbital mechanics, Earth-Moon system, tides, nature of light, telescopes/detectors, our solar system and others
We will begin stellar astrophysics if time permits.

Topics covered:
stars, stellar structure, interstellar medium, star formation, the Milky Way, galaxies, cosmology

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

If you miss a test and you give me a week's
advance notice with a documentable reason,  the make-up may be an
oral exam. Missed quizzes may be excused, with documentation, with their weight put on the midterm or final exam.  
General test policy is that once you leave the room, you can't come back in.
You are permitted to help each other in groups, but you must turn in your own work.
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.