Astronomy 101: Introduction to Astronomy

NASA/JPL-Caltech/C. Martin (Caltech)/M. Seibert(OCIW)

Fall 2008

Prof. Kannappan's Website * Department of Physics & Astronomy * UNC Chapel Hill

In This Page:
Overview	Course Description	Class Schedule	Homework and Quizzes	Getting Help
Exams	Grades	How to Succeed in this Course	Web Resources	Assignments and Materials

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1. Overview

Professor	Sheila Kannappan: office hours Mondays, 5-6pm, Phillips 290 and by appointment (sheila@physics.unc.edu)
TA	JoEllen McBride: office hours Mondays, 5-6pm, Phillips 290 and by appointment (mcbridej@physics.unc.edu)
Class Hours and Venue	Tuesdays and Thursdays 8-9:15am, Phillips 215
Quizzes	iClicker quizzes are given at the beginning of each class Note that the Physics & Astronomy Department has a permanent set of iClickers to be used in class, so you do not need to buy an iClicker. If you have one, you may use it instead of ours. We will register iClickers as a class on 8/21.
Exams	Midterm: Thursday, Oct. 2^nd, in class Final: Saturday, Dec. 6^th, 8-10am, location TBA
Textbook	Universe, 8^th Edition (Roger A. Freedman & William J. Kaufmann III)
A101 discussion boards	Discussion boards for content and logistics questions are available in Blackboard.

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2. Course Description

This course covers the historical foundations of astronomy, the methods and tools of astronomical science, and the structure and evolution of stars, planets, galaxies, and the Universe as a whole. The course is intended for non-science majors, so there are no college-level prerequisites, but typical high school algebra and science preparation are assumed. Astronomy 101 does not require enrollment in Astronomy 101L, the astronomy laboratory course, but you may not take A101L without taking A101 as well.

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3. Class Schedule

The class schedule is given below, along with the relevant textbook chapters. Students are not generally required to read the listed chapters in their entirety; required sections will be noted in the homework. Additional, non-textbook material will also be provided.

CLASS	DATE	TOPICS	CHAPTERS
1	Aug 19	INTRODUCTION & OVERVIEW	1
2	Aug 21	MATH TOOLS & iCLICKER PRACTICE; MISCONCEPTIONS	1
3	Aug 26	NAKED EYE ASTRONOMY	2, 3
4	Aug 28	NAKED EYE ASTRONOMY	2, 3
5	Sep 2	THE RISE OF ASTROPHYSICS	3, 4
6	Sep 4	THE RISE OF ASTROPHYSICS	3, 4
7	Sep 9	NEWTON'S LAWS	4
8	Sep 11	LIGHT, OPTICS, & STARS	5, 6, 16, 17
9	Sep 16	LIGHT, OPTICS, & STARS	5, 6, 16, 17
10	Sep 18	LIGHT, OPTICS, & STARS	5, 6, 16, 17
11	Sep 23	ORBITS	4, 5, 17
12	Sep 25	ORBITS	4, 5, 17
13	Sep 30	REVIEW
14	Oct 2	MIDTERM EXAM, in class
15	Oct 7	ASTROBIOLOGY	28
16	Oct 9	STAR & PLANET FORMATION	7, 8, 18
17	Oct 14	OUR SOLAR SYSTEM	7, 8, 10
	Oct 16	FALL BREAK
18	Oct 21	LIFE & DEATH OF STARS	19, 20, 21
19	Oct 23	BLACK HOLES	22
20	Oct 28	BLACK HOLES	22
21	Oct 30	DISCOVERING GALAXIES	23, 24
22	Nov 4	THE EXPANDING UNIVERSE	24, 26
23	Nov 6	GALAXY EVOLUTION I	19, 23, 24
24	Nov 11	DARK MATTER	23, 24
25	Nov 13	GALAXY EVOLUTION II	23, 24, 25, 27
26	Nov 18	THE MILKY WAY & THE LOCAL GROUP	23, 24
27	Nov 20	COSMOLOGY I	26
28	Nov 25	COSMOLOGY II	28
	Nov 27	THANKSGIVING
29	Dec 2	REVIEW
	Dec 4	NO CLASS
30	Dec 6	FINAL EXAM, 8-10am, room TBA

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4. Homework and Quizzes

Homework will be assigned for each class, in the form of reading to prepare for class and answering review questions/problems on the reading and/or recent class material. The homework will not be graded, but a quiz on the homework will be given at the beginning of each class (occasionally when a quiz is impractical, a 100% score will be awarded for written evidence of completion of the assignment). If you do the homework, you should find the quizzes easy. The quizzes will be similar, but not identical, to the homework.

Completing the homework is essential to get a good grade in the course, for three reasons:

1. iClicker quizzes count for 1/3 of the final course grade.
2. It is much easier to get a high score on the homework quizzes than on the exams.
3. Doing the homework will prepare you for the exams.

Occasionally extra iClicker quizzes may be given during class to review material covered in class. Being in class and paying attention will allow you to perform well on these quizzes.

If you are sick or perform poorly on a quiz, do not despair! Regardless of the reason, your lowest five quiz scores for the semester will be dropped. Therefore, no make-up quizzes will be allowed for any reason.

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5. Getting Help

Office hours are Mondays 5:00-6:00PM in Phillips Hall 290 with both the instructor and TA available to help. We are also available after class and by appointment.

A101 discussion boards on UNC's Blackboard system: This is the best place to submit questions about course material or logistics. Emails on these topics will not be answered directly, rather the questions and answers will be posted anonymously on the discussion board.

You are of course welcome to email or call Prof. Kannappan directly with emergencies or confidential issues.

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6. Exams

There will be a midterm exam on October 2^nd during the regular class period. The final exam covers the whole course with emphasis on the second half and will be on December 6^th at 8am. Note that this time is scheduled by the University. Make-up exams will be arranged for those who have an excused absence for either the midterm or the final exam.

Only students unable to attend the regular exams because of a class conflict, a medical/family emergency (which must be documented), or other serious and unforeseen event (which must be documented) will be allowed to take make-up exams.

All exams will be closed book and closely modeled on homework and in-class material such as think-pair-share questions. Calculators are not required but are allowed.

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7. Grades

The course grade will be determined by:

Midterm Exam:	1/3
Final Exam:	1/3
iClicker Quizzes:	1/3

Note that the maximum score that can be obtained from exams alone is 67%. Therefore it is impossible to get a good overall grade without attending class, in which the iClicker quizzes are given. (See Homework & Quizzes.)

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8. How to Succeed in this Course

• Attend all classes and come prepared for the quizzes.
• Always bring your voting card to class. You may use our iClickers or bring your own (registration of iClickers is Thursday 8/21). It is not necessary to bring the textbook to class.
• Ask questions and actively participate in interactive learning activities.
• Keep the cell phone and laptop turned off.
• Do not assume the textbook is ''what you need to know.'' It contains much more material than you will be expected to learn, and it contains incorrect material. Chapters noted in the schedule are listed for general reference, whereas the homework given in class will assign only specific sections.
• Pay attention to lecture or non-textbook material relating to the methods, outlook, and values of science and scientists. This material goes beyond your textbook and is central to the course.
• Uphold the Honor Code.
• If you need extra help, come see us outside of class!

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9. Web Resources

UNC Honor Code

Multicultural Astronomy

The Orion Star-Forming Region (animation of gas seen in radio waves over visible constellation)

The Orion Nebula (close-up of the stellar nursery in the dagger of Orion)

Powers of 10 with Galaxy Song from Monty Python

A Nice Tutorial on RA and Dec for those in the A101 Lab Class

Why the Moon Turns Red During a Lunar Eclipse

Animation of the Wandering Path of Mars as Viewed from Earth see bottom of page (other cool animations up top!)

Retrograde Motion Simulator: you can switch which planet you're looking from & at

Contact movie introduction

Behind the scenes the making of the "Pillars of Creation" image of the Eagle Nebula

Orion Movie fly-through movie of the Orion Nebula from the San Diego Supercomputer Center

Special Relativity Clocks Slowing animation

Einstein's New Way of Thinking about Gravity video

Truth and Lies about Black Holes Chandra X-Ray Telescope Podcast

Spaghettification

Milky Way in 3D

zoom out from Earth through Milky Way and beyond

Expansion of the Universe activity done in class

Merging Galaxies video with stars, gas, dust

The Mice real and simulated galaxy merger from Josh Barnes (IfA)

LHC rap the Large Hadron Collider rap -- scientifically accurate!

Cosmic Web simulation showing the growth of large scale filaments, clusters, and voids over cosmic time

2MASS All-Sky Survey observed structure in the Cosmic Web from z=0-0.1

First Structure Formation simulation; four panels including temperature and metallicity (B. Oppenheimer)

Black Hole Feedback illustrated in simulation of spiral-spiral merger (di Matteo, Springel, & Hernquist)

Bottom-Up Merger Formation of a Cluster simulation without gas (Dubinski)

Bottom-Up Merger Formation of a Spiral Galaxy simulation with abundant gas (L. Mayer; nbodyshop)

This list will grow; come back and visit often.

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10. Assignments & Materials

All assignments are due in or before class on the date shown unless otherwise noted. They are not directly graded unless otherwise noted.

Thursday, August 21

Read Ch. 1-5, 1-6, 1-7, and "Cosmic Connections" box on p. 16

Do problems 1-13, 1-22, 1-28 (ANSWER in back of book), 1-36 (ANSWER in back of book) and the following:

Find two astronomical beliefs from ancient or foreign cultures on the web, one that you accept and one that you don't, and email the links to your instructors via Blackboard. In Blackboard, click on ''Communication'' and check the Discussion Board for the secret phrase; then DO NOT REPLY but go to ''Send Email'' and start a new message to both the Professor & TA; add the secret phrase to your email so we know you've found Blackboard! Your email should include a brief phrase describing each astronomical belief and indicate which one you accept and which you don't. You will get one 100% quiz score for sending the two links plus the secret phrase on Blackboard, and we will discuss your choices in class next time. HINT: see Multicultural Astronomy link above.

Tuesday, August 26

Do problems 1-39 and 1-49 (introduction to Starry Night software)

Read Ch. 2-4, 3-1, 3-2*, 3-3

Do problems 2-8, 2-12, 3-7 and the following:

*For 3-2, read only the first four paragraphs. Note that another way of describing the moon's motion would be that it does not rotate from its own point of view, like a person walking in a circle who always walks nose-forward. In contrast, the text describes rotation or lack thereof from an outside observer's point of view, as if hovering in space above the Earth and moon. If you were to rewrite the caption to Fig. 3-4 from the moon's point of view, how would you describe the rotation or lack thereof in each panel?

Thursday, August 28

Lightly skim Ch. 2-1, 2-3, and 2-8 [ignoring all jargon & ignoring box 2-2]
Read 2-5 [skipping box 2-1] and 2-6
Do problems 2-13, 2-14, 2-18, 2-43, and Starry Night exercise 2-64

Tuesday, September 2

Read Ch. 3-6 [ignoring box 3-2] and 4-1

Do problems 3-22, 3-23, 3-24, and 3-32 [ANSWER in back of book]

[Hint: What is the moon's speed in units of degrees/day if the lunar month is 27.32 days?]

Thursday, September 4

Read one-page handout on great figures in early modern astronomy

Browse 4-2 & 4-3 to make sure you know handout terms in bold (except Newton's Laws, saved for next week)

Read 4-4 [ignoring box 4-2]

Read Gingerich article on Kepler [reproduced by permission for educational use in its entirety only]

[NOTE: you may need to download and save this article, then rotate it within Acrobat Reader]

Do problem 4-16 and answer the following:

How does the Gingerich article differ from the book's discussion of Kepler in section 4-4?

Tuesday, September 9

Read 4-6, 4-7 (ignoring box 4-4), and Cosmic Connections on p. 88

Do problems 4-22, 4-26 (ANSWER in back of book), and 4-43 (ANSWER in back of book)

NOTE: Wednesday, September 10

optional Newton's Laws Review Session 5-6pm Phillips 215

Thursday, September 11

Read 5-2 and 17-2 (ignoring box 17-2)

Lightly skim 17-3 (ignoring box 17-3)

Do problems 5-3 (ANSWER in back of book), 5-7 (ANSWER in back of book), 17-41, 17-42, and 17-43

Tuesday, September 16

Read 5-3 (including skimming box 5-1 briefly) and 5-5 (ignoring boxes 5-2 & 5-3)

Read Ch. 16 Intro & 16-1 (skipping box 16-1 and skipping Cosmic Connections)

Read 17-4 (ignoring box 17-3)

Do problems 5-9, 5-18, 16-6, 17-52 plus 6-23

Thursday, September 18

Read 5-6 (emphasizing Kirchoff's Laws + Spectroscopy and skipping box 5-4)

Skim 5-7 (lightly -- just remind yourself what is an atom/nucleus/electron)

Read 5-8 (ignoring box 5-5), 17-5, and 17-7

Do problems 5-32, 5-36, 17-15, 17-20

Tuesday, September 23

Do problem 17-19

Read 5-9

Study Figures 17-20, 17-21, and 17-22 (read the captions; you need not read the accompanying textbook sections if you understand what the figures are showing)

Do problems 5-22, 5-23 (careful!), and 17-39 (note the error in part c, it says Halpha but means Hbeta; ANSWERS to parts a and c in back of book)

Download all past class slides and assess your understanding (we'll vote on review topics in class for the 9/30 Review)

Thursday, September 25

Read pp. 200-203 starting from paragraph 4 ("radial velocity method"); ignore Fig. 8-19

Study Fig. 8-17 carefully (the unit "M_J" = mass of Jupiter)

Answer the following:

How are the masses and orbits of planets discovered by the radial velocity method surprising? What ideas does your text offer to explain this? How might selection bias, in the form of the ability to detect the planet at all, play a role? HINT: think about how the masses and orbits of extrasolar planets affect the amplitude of the Doppler wobble.

Tuesday, September 30

Study everything (class slides, homework, handouts)

Review by doing problems 3-46, 4-13, 4-17, 4-29, 5-21, 5-33 [ANSWER in back of book], 5-38 [ANSWER in back of book], 17-34 [ANSWER in back of book], and 17-44

Get a scantron form and #2 pencil for the midterm

Submit the Extra Credit described in Class 9 any time up until the midterm, by either email or hardcopy (see Selection Effects slide in Class 9 slides on Blackboard)

Tuesday, October 7

Browse all of Chapter 28 for fun.

Visit these URLs to study the Drake Equation:

http://www.pbs.org/wgbh/nova/origins/drake.html

http://www.pbs.org/lifebeyondearth/listening/drake.html

Answer the following based on these URLs:

Pick the two terms in the Drake Equation that seem most uncertain to

you and the two terms that seem most accessible to scientific inquiry.

Would it be possible to scientifically test & validate the Drake

Equation? Explain.

Thursday, October 9

Read Box 5-4

Read 18-2 and p.491 "How Stars Are Born"; study Fig. 18-17

Do problems 18-8, 18-11, 18-13, 18-28 (browse chapter headings to help answer 18-28; three ways is enough)

Read 7-1 and study table 7-3

Do problems 7-2, 7-3, 7-4

Study Table 8-1, Fig. 8-10

Read 8-6, 8-7 (partly already read), and p. 199 "Formation of the Solar System"

Do problems 8-17, 8-19

Tuesday, October 14

Read 7-2, 7-5, 8-2, 8-3 (with Box 8-1), and skim 10-5

Do problems 28-24, 7-10, 7-32, 8-4, and 8-6

Answer the following questions:

How are the satellites of Earth and Pluto similar/different?

Consider both their properties and their possible formation histories.

Does Earth satisfy the IAU definition of a planet?

(Find it here: http://en.wikipedia.org/wiki/Definition_of_planet)

Tuesday, October 21

Using Chapters 19, 20, and 21 as a reference to help with unfamiliar

terms, read http://en.wikipedia.org/wiki/Stellar_evolution in detail.

Also study Cosmic Connections p. 534 and review 17-9 from "Main

Sequence Masses..." to the end, including Cosmic Connections p. 459.

Do problems 19-4, 19-6, 20-7 (note "planetary nebulae" have nothing to

do with planets!), 20-11, 20-16, 20-26 (study/compare Figs. 20-14 &

20-21 for this problem), 20-31, 21-32, and 21-50.

Thursday, October 23

Read 4-8, 22-1, 22-2, 22-6 (first four paragraphs, just two columns),

Box 22-2, Cosmic Connections p. 595, and 22-8.

Do problems 4-30, 22-2, 22-4, 22-7, 22-10, and 22-24.

For problem 4-30, also comment on how tidal forces affect objects near a black hole.

Tuesday, October 28

Read 22-3 (skimming lightly over the middle parts on Cygnus X-1 and Other BH Candidates), 22-4 (skim for main ideas), 22-5, and 22-9.

Do problems 22-15, 22-32, 22-42, and 22-44 (hint: use the "motions find mass" equation from Class 12).

NOTE: Wednesday, October 29

optional Stars & Planets Review Session 4:30-6pm Phillips 215

Thursday, October 30

Read Ch. 23 Intro and 23-1, Ch. 24 Intro and 24-1, 24-2.

Do problems 23-2, 23-3, 24-2, 24-3, 24-11.

Tuesday, November 4

Read 24-5 (do NOT read Box 24-2 and skim "Pinning Down..." very lightly), plus 26-1, 26-2, and 26-3

Do problems 24-16, 26-2, 26-4, 26-5, 26-9, and 26-11

Thursday, November 6

Read 19-5, 23-2, and study Figs. 23-15 and 23-16

Read Ch. 23-5 selectively (read first paragraph; skip subsection on Winding; read first paragraph only in subsection on Density Waves; examine Figs. 23-22 and 23-23; read last subsection on self-propagating star formation)

Study Cosmic Connections Box on p. 625

Skim 24-3 lightly (ignore "Caution" on p. 642 and paragraph right after that -- both are misleading)

Read Cosmic Connections Box on p. 657 and the last subsection of 24-7 on Galaxy Interactions and Spiral Arms

Answer problems 23-7, 23-9, 23-13, Starry Night Exercise 24-61, 24-24, and the following:

What are three ideas for how spiral arms form?

Tuesday, November 11

Read sections 23-4 (refer to 23-3 if you're confused about the 21 cm line -- all you need to know is that it is the main emission line from neutral atomic Hydrogen), 24-6, and 24-8

Do problems 23-17, 23-20, 24-47, 23-21 (answer using both Chs. 23 & 24), 24-21

Thursday, November 13

Read sections 24-9, skim 26-4 and 26-5 with closer attention to "When the First Atoms Formed", study Fig. 27-11, read 27-6 (skipping the subsection on the Jeans length), and read the "Key Ideas" summary of Ch. 25 on p. 687

Do problems 24-29, 26-24, 25-22, 25-24, 27-22, 27-23 and answer the following:

Put these events in order: primordial Big Bang nucleosynthesis, reionization, recombination, formation of population III stars. Which of these events do we see in the Cosmic Microwave Background?

Tuesday, November 18

Skim 23-3 very lightly, with attention to the information on page 613 about the Local Bubble and on page 616 (including Fig. 23-16) about the Sun's location and the structure of the Milky Way.

Answer the following:

What is the Local Bubble and how did it likely form? Is your answer consistent with the position of the Sun relative to the spiral arms?

Read 23-6.

Do problems 23-35 and 23-47 [ANSWERS for both questions are in the back of the book]. For 23-35, you should use the information in the chapter to compute the period (review section 23-4). For 23-47, replace the words "sum of the masses of Sagittarius A* and the star" with the words "mass of Sagittarius A*" and use the motions find mass equation. Compare the periods in problems 23-35 and 23-47.

NOTE: Wednesday, November 19

optional Galaxies Review Session 4:30-6pm Phillips 215

Thursday, November 20

Read 26-6, 26-7, and 27-1. Do problems 26-3, 26-27, 26-45 (part c only), 27-1, and 27-4.

Read Neil Tyson's article In Defense of the Big Bang and answer the following:

How is the word "theory" different from the word "law" according to Tyson? Why does this matter in evaluating Big Bang Theory?

Tuesday, November 25

Watch the first half (5 min 32 sec) of this video on the Moon and listen for answers to these questions:

1)What caused the Earth's rotation, giving us days and nights?

2)What caused the Earth's tilt, giving us seasons, and what stabilizes that tilt from wandering chaotically?

3)How might the abundance of life on Earth vs. the apparent lack of life on Mars be understood by comparing the moons of Earth and Mars?

Now read this article on recent results from Spitzer and answer the following questions:

1) What do the scientists in the article claim about moons around extrasolar planets?

2) Do you agree with how they selected their sample? Will there be a selection bias?

3) Based on both the video and the article, would you want to modify the Drake Equation?

Finally, read the Cosmic Connections Box "Habitable Zones for Life" on p. 756 of your text. Remind yourself of the definitions of the Copernican and Anthropic Principles from your class notes. Which principle supports extending the Habitable Zone concept to include whether there is a Moon like ours? How could this concept be extended to ask why dark energy has the value it has, if our Universe is one of many in a "multiverse"?

Tuesday, December 2

Extra Credit Scavenger Hunt:

Must be submitted as plain text email by the end of the day. Each part counts equally.

Brief answers are encouraged; complete sentences are *not* needed.

(1) Two of the closest stars to Earth that are candidates for going supernova in our lifetimes are Betelgeuse and IK Pegasi. For each one, browse the web to find its star/star-system type and the type of supernova it will become (i.e. thermonuclear or core-collapse).

(2) Open Starry Night, find the Trifid Nebula, and zoom in. What two other nebulae/clusters are located within 1.5 degrees (hover your cursor over them to get their names)? Based on the descriptions and colors of these three objects, list them in order from the earliest to the most advanced stage of star cluster formation. (Hint: remember the color of the gas in the Pleiades open star cluster, which has already started blowing out its gas and dispersing.)

(3) Go to Astronomy Picture of the Day (apod.nasa.gov) and find the pictures for your birthday in recent years (click "Archive" then type the day, e.g. "January 12"). Choose one you like and paste the URL plus the entire caption into your email, along with 1-2 sentences describing something you learned in class related to this picture (in a very general way) that is not mentioned in the caption. Please indicate your added sentences (e.g., "I learned:").

Exam Week

FINAL EXAM REVEW in class Tuesday, December 2

Office Hours Wed-Thurs-Fri 5-6pm (not Monday)

Review Problems (optional and NOT comprehensive -- study past HW & classwork as first priority, then work on these, starting with topics you most need to review):

Pre-Midterm: 2-17, 3-25, 4-9, 4-20, 4-38, 5-37, 5-41, 6-28, 8-22, 17-3, 17-16, 17-18, 17-28, 17-46

Post-Midterm: 7-11, 7-22, 8-15, 8-23, 8-25, 18-7, 18-16, 19-1, 19-8, 20-15, 21-31, 22-5, 22-8, 22-49, 22-51, 23-1, 23-26, 23-36, 23-42, 24-7, 24-18, 24-39, 26-18, 26-19, 27-18, 27-24, 28-4

FINAL EXAM December 6 Phillips 215 8-10am

This list will grow; come back and visit often.

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