INST 2403 The Expanding Universe

1. INST 2403The Expanding Universe Dr. Uwe Trittmann Utrittmann@Otterbein.edu Office: Science 107 Phone: 823-1806 Secretary: Celina Chou (823-1316), Science 236 Office Hours: MW 3-4pm or by appointment.

2. Course Materials • Textbooks: • Investigating Astronomy: A Conceptual View of the Universe, 2ndEdition, by Slater and Freedman (W.H. Freeman 2014) • Lecture Tutorials for Introductory Astronomy, 3rd ed., by Edward E. Prather, Tim P. Slater, Jeff Adams, and Gina Brissenden (Benjamin Cummings) • Need WebAssign access, too! • Course Web Page: http://faculty.otterbein.edu/utrittmann/is2403-01/ • Observatory schedule, lecture notes, study guides, the syllabus, notices, online resources, …

3. Why we are here • For the love of Astronomy • We are all going to make a good faith effort in teaching and learning

4. Assignments and Grading

5. Rooftop Visit & Starry Mondays • Come to experience the night sky with your own eyes • Write a short summary of your experience Photos taken with student’s iPhone through telescope eyepiece!

6. Activities • Small-group work • In-class discussion • active learning of important concepts • Show up, participate, learn, receive credit!

7. Participation • Dito: Show up, participate, learn, receive credit • Be prepared to think of an answer when prompted • Have you read the memo?

8. Participate by Peer Instruction • Peer instruction is learning by instructing your fellow students and being instructed by them • The process involves 6 steps: • Mini-lecture by course instructor • Conceptual multiple-choice question is put up • Flash-cards are used to “poll the audience” • A few minutes of discussion between students • “Final answer” via flash-cards • The instructor explains the correct answer

9. Who was the first man on the Moon? • Yuri Gagarin • Buzz Aldrin • Neil Armstrong • John Glenn

10. Concept Questions • Concept questions maybe easy to answer, but are not simple • You need background knowledge to answer them • They teach you how to use facts and knowledge to find the answer to a problem • They test if you got the concept rather than just knowing facts

11. It is New Moon. In one week, what will the phase of the Moon be? • New Moon • First Quarter Moon • Full Moon • Last Quarter Moon

12. Why it works • Carefully chosen questions • It is easier to be convinced and to convince if the reasoning is sound and hence the answer correct Right to right Wrong to right Right to wrong No 2nd answer wrong to wrong How answers are revised in a typical question

13. Weekly Homework • Will use WebAssign, an online homework system • Password & username: first initial plus last name all lowercase, e.g. utrittmann • HW due on Friday evenings

14. iSkylab • Equivalent of a term paper, but more experimental • 4 different stages • Start early - weather is always a factor • Ask questions! • Due after each of the midterm exams

15. Welcome to the Class! • Astronomy is an exciting topic • Get some sense why scientists love what they are doing

16. Sorry, this is not your major course, but it is a college-level course  • Expect to work at least as hard for this course as for your major classes; 2hrs out of class per class • Let’s take a look at 1st grade-level work 

17. Jupiter By: Arthur Trittmann

18. My planet is Jupiter • Jupiter is the biggest planet in the solar system! • Jupiter is 88,650 mi. around! • Jupiter has a hurricane that has lasted more then 400 years! • Jupiter has rings made of ice, rock, and dust.

19. My planet’s weather. Jupiter’s atmosphere has storms that go 369 mi. per hour! Jupiter doesn’t have life because it is too cold, and it is a gas giant.

20. My planet’s orbit. Did you know Jupiter is the fastest spinning planet? Jupiter comes from the name of a Roman god. Did you know Jupiter is the son of Saturn?

21. Interesting facts I learned about my planet. • One day on Jupiter is 10 Earth hours. • One year on Jupiter is 12 Earth years! • Scientists have a future mission, to send a space probe to Europa to find life. • Ganymede is Jupiter’s biggest moon!

22. The whole universe in 14 weeks ?! • The focus is on concepts, not facts; on the methods and tools of science: • How do we know? • How can we measure it? • How can we predict it?

23. A Glance at the Course Content: Top Down • The Universe is accelerating its Expansion • How do we know? • Supernovae are dimmer than they should be in a standard expanding universe • What is a supernova? What is a standard universe? • SN are massive stars exploding at the end of their lives • How do we know?

24. Top Down • Stars are hot gas balls that fuse H to He; they run out of fuel • How do we know? • Can measure spectra, compare to the sun • What is a spectrum? How does the sun “work”? • The sun is 300,000 more massive than the earth, consists of H & He, produces a lot of energy  must be fusion • How do we know?

25. Top Down • Measure distance to sun, use Newton gravity to obtain mass, measure H & He spectra in lab • How do we measure distance to sun? • What is Newton gravity? • What are spectra in the lab? • Use Kepler’s laws, observe special configuration of planets from different positions on earth • What are Kepler’s laws? How big is Earth?

26. Top Down • Planets go around the sun in ellipses • How do we know? • The observer’s view is different for different places on Earth  radius • How do we know Look at the sky!

27. Activity: The Sun’s Shadow • Measuring the length of the shadow, we can infer the sun’s position