ASTR100 (Spring 2008) Introduction to Astronomy Prof. D.C. Richardson Sections

Professor:Dr. Derek C. Richardson Phone: Office:CSS 1249 Office Hours:W 11h-12h, or by appointment. Course web page: Textbook:The Essential Cosmic Perspective (4 th ed, Media Update), Bennett et al. Textbook web page: Astronomy 100 – ASTR100

The observation and study of everything in the universe except the Earth (but we’ll talk about the Earth too – it’s the best understood planet). Oldest of all the sciences – but we’ll be talking about “modern” astronomy. What is astrophysics? What is astronomy? Application of physical laws to understand celestial objects.

The Earth

The Moon

Artist’s view of the Solar System

© Anglo-Australian Telescope Board ( Stars & Gas

Artist’s view of our Galaxy

Remote Galaxies seen by HST

An atom (helium)

Basic logistics, organization, expectations and rules of the course…

Course syllabus and lecture plan Log in to ELMS/Blackboard: READ THE SYLLABUS! The syllabus is our mutual contract. Complete the ASTR100 Contract quiz online (click on the “Homework” button to see it).

Class web page Announcements Syllabus Lecture plan Homework Extra stuff to help you out MasteringAstronomy.com Cool links NOTE: Each discussion section also has its own ELMS course page! You can check your grade there.

Discussion Sections (CSS 2400) SectionFirst MeetingTimeTA Name 0101Mon Feb 49:00 amMichael McDonald 0102Mon Feb 410:00 amMichael McDonald 0103Mon Feb 4noonMatthew Zagursky 0104Wed Feb 69:00 amNaomi Luis 0105Fri Feb 89:00 amNaomi Luis 0106Fri Feb 8noonAshley King Meet in CSS 2400 (newer wing of CSS building)

Map for sections Sections meet here We are here

The Computer and Space Sciences building is a confusing labyrinth! CSS (Computer & Space Sciences bldg) 2400 is in the NEWER wing of CSS… Older wing of CSS is 60’s-era brick building (my office, TA offices). Newer wing of CSS is 90’s-era glass-faced building just up hill from older CSS wing. Go up one floor from entrance floor. CSS 2400 is entered from near atrium.

This is a CORE course… This course is intended for non-science majors. No more than modest high-school science and math required. This course satisfies CORE Distributive Studies requirement for a non-lab physical science course (Code PS). For a lab physical science course (PL): You MUST take ASTR 111 simultaneously with this course, OR take ASTR 101 instead of this course. You cannot get credit for both ASTR 100 and ASTR 101.

Lectures Provide a framework for reading, homework, discussion sections. Not a substitute for anything above! Based on material in the book, but expands on some things, skips others. Demonstrations of basic principles. Notetaking: don’t concentrate on details (those are in the book), just on the broader connections.

Course Expectations Attendance Attend all lectures and discussion sections! Significant grade is awarded for participation and activities in discussion sections. Exams and homework are based on lectures, textbook, and discussion sections. There will be unannounced in-class exercises. If you have to miss a class, borrow notes from other students.

Course Expectations Preparation Be prepared (see schedule)…schedule  Preview reading assignment before class.  Read it again more carefully after class. Study your class notes after class…  Ask questions! Don’t fall behind, don’t cram. Talk to TA or prof before you get in trouble.  That’s what office hours are for!  Take advantage of them!

Course Expectations Mathematics and physics Modern astrophysics is as technical as it gets… there is lots of very hard math and physics! We will avoid the really technical stuff, but there will be high-school level math (algebra & geometry). Expect it! If you get stuck, ask for help before you fall behind!

Grading: weights ComponentPoints Homework130 Discussion section130 In-class exercises 20 Midterm exam 175 Midterm exam 275 Final exam120 TOTAL550

Grading: boundaries The optional plus/minus grading system will be used in this course. Any adjustment to boundaries will be to lower percentages, never to raise them. Letter gradePercentagePoints A-, A, A % B-, B, B+80-90% C-, C, C+70-80% D-, D, D+60-70% F0-60%0-329

Midterms and final exam Midterms (both in class, in this room): 1.Tuesday, March 4. 2.Tuesday, April 15. Cumulative final exam (in this room): Friday, May 16, 8 am-10 am. Midterms and Final: Cover lecture, textbook, discussion section. Closed book, no notes or calculators, no walkmans, no mobile phones, no PDAs, etc. Multiple choice, short answer/essay, probem- solving questions. Bring pencils, picture ID; we may check ID before you hand in exams.

Missing exams, classes, and discussion sections Not allowed except under special circumstances. See Attendance and Assessment Policy section of Schedule of Classes for valid reasons.Attendance and Assessment PolicySchedule of Classes Contact me as soon as you know you will miss an exam (or class with homework or possible in- class exercise) when you have a valid reason. Planned absences due by February 6. Documentation is required. You must contact me promptly to schedule make-up. See syllabus for more info.

Discussion Sections 130 points of course grade based on this important part of the course. 50 minutes long, meet once per week. Run by TA with general guidelines from me. TA has my full authority! Review lectures, present problems and material not in lecture. Quizzes and exercises. You must attend your scheduled section – change through Registrar only.

Homework Assignments Assigned in class/on web, solutions on web. Due in class at 9:30 am. Must be typed (or neatly written) and stapled. Will not be accepted after the end of class. Read syllabus for details! First homework can be found on ELMS and is due a week from today (Feb 5). You may discuss homework with classmates, but final write-up must be in your words. No copying! List sources!

Extra Credit There will be no extra-credit papers. I may ask questions or give assignments worth bonus points. Extra-credit questions may appear on homework. Your TA may award extra credit in section.

University of Maryland Honor Pledge I pledge on my honor that I have not given or received any unauthorized assistance on this examination.

Academic Integrity This is serious!!! Abide by Code of Academic Integrity. Academic dishonesty includes: Cheating. Plagiarism. Facilitating. Fabrication. A few specific examples:  Copying homework from a friend or from a book.  Allowing your work to be copied.  Cheating on tests.

Academic Integrity We may refer cases to the Student Honor Council… You may get an XF course grade. For further information: See syllabus. Read Code of Academic Integrity  In Academic Info section of Schedule of Classes  Or in Undergraduate Catalog  Or on the web versions of these.

ASTR100 (Spring 2008) Introduction to Astronomy Our Place in the Universe Prof. D.C. Richardson Sections

Our Modern View of the Universe

What is our physical place in the universe? Our “Cosmic Address”

A large, glowing ball of gas that generates heat and light through nuclear fusion Star

Planet A moderately large object that orbits a star; it shines by reflected light. Planets may be rocky, icy, or gaseous in composition. Mars Neptune

Moon (or satellite) An object that orbits a planet. Ganymede (orbits Jupiter)

Asteroid A relatively small and rocky object that orbits a star. Ida

Comet A relatively small and icy object that orbits a star.

Solar (Star) System A star and all the material that orbits it, including its planets and moons

Nebula An interstellar cloud of gas and/or dust

Galaxy A great island of stars in space, all held together by gravity and orbiting a common center M31, The Great Galaxy in Andromeda

Universe The sum total of all matter and energy; that is, everything within and between all galaxies

The Scale of the Universe

How big is Earth compared to our solar system? Let’s reduce the size of the solar system by a factor of 10 billion; the Sun is now the size of a large grapefruit (14 cm diameter). How big is Earth on this scale? A.an atom B.a ball point C.a marble D.a golf ball

How big is Earth compared to our solar system? Let’s reduce the size of the solar system by a factor of 10 billion; the Sun is now the size of a large grapefruit (14 cm diameter). How big is Earth on this scale? A.an atom B.a ball point C.a marble D.a golf ball

The scale of the solar system On a 1-to-10 billion scale: Sun is the size of a large grapefruit (14 cm) Earth is the size of a ball point, 15 meters away.

Relative Sizes of the Planets

How far away are the stars? On our 1-to-10 billion scale, it’s just a few minutes walk to Pluto. How far would you have to walk to reach Alpha Centauri? A.1 mile B.10 miles C.100 miles D.the distance across the U.S. (2500 miles)

Answer: D, the distance across the U.S.

How big is the Milky Way Galaxy? The Milky Way has about 100 billion stars. On the same ten billion-to- one scale…

Suppose you tried to count the more than 100 billion stars in our galaxy, at a rate of one per second… How long would it take you? A.a few weeks B.a few months C.a few years D.a few thousand years

Suppose you tried to count the more than 100 billion stars in our galaxy, at a rate of one per second… How long would it take you? A.a few weeks B.a few months C.a few years D.a few thousand years

How big is the (Observable) Universe? The Milky Way is one of about 100 billion galaxies stars/galaxy x galaxies = stars As many stars as grains of (dry) sand on all Earth’s beaches…

Now let’s step through the Universe in powers of 10: