1. 7.1: The Earth’s Role in our Solar System

2. Science Starter 1. Explain how the Earth moves around in space 2. If the planet we live on is constantly in motion, does that mean we are moving right now? Explain. 3. Why do we experience seasons on Earth? 4. Do you think other planets experience seasons? Why or why not?

3. Agenda  Science Starter  Black Holes  Today’s Notes (15)  Stations  Exit Ticket

4. Black Holes: What Happens? Neil Degrasse Tyson Astrophysicist Hosted Show, Cosmos: A Spacetime Odyssey Graduated from Harvard & Columbia Gave lectures on astronomy at the age of 15

5. Day 2 Earth’s Role in Space

6. Lesson Essential Question How does the Earth move? (Rotation, Revolution, Precession, Nutation)

7. Notes on the Universe The universe is made of galaxies which are made of many stars. Some stars have planetary systems similar to our solar system. Earth is a satellite planet of one particular star (our sun)

8. The (whole) Earth moves in 3 ways. The Earth: 1.Rotates (Rotation) 2.Orbits 3.Revolves (Revolution)

9. The earth rotates on its axis. Rotates = spins. The earth makes 1 full rotation every 24 hours.

10. The axis of the Earth is tilted at an angle of 23.5 degrees. The axis always points towards the North Star.

11. We have day and night because of the Earth’s rotation.

12. DRAW A PICTURE OF THE EARTH TILTED ON ITS AXIS…

13. The Earth also revolves around the sun in an elliptical orbit. The earth makes one full revolution around the sun every365.25 days. 365 days = 1 year

14. Kepler’s Three Laws of Planetary Motion (A Summary) 1. Each planet takes an elliptical path around the sun 2. Planets travel faster when they are close to the sun and slower when they are farther away from the sun 3. The amount of time needed for a planet to revolve around the sun is proportional to the planet’s distance from the sun B C A

15. Precession  The direction this axis of a planet is pointing in will change, but the tilt will not change.  This will change the stars near the pole but will not change the seasons (as long as the angle of the tilt, 23.5 in the case of Earth, stays the same)

16. Nutation  Nutation happens when the axis of a planet starts to wobble (do the wobble!)  The angle of the axis will change during nutation ½ degree one direction or the other  Nutation happens over the course of 18 years  Nutation is a direct result of the moon (or moons) of a planet

17. Stations There are 3 stations around the room A.Reading Station (Groups 1-2) B.Videos (Groups 3,5,8) C.Hands on (Groups 4,6,7) You will spend 15 minutes at your designated station. You may work alone or in groups At the end you should be able to answer the following questions…

18. Stations Questions to answer while you work: 1.Why does the Earth experience precession? 2.Why does the Earth experience nutation? 3.What do nutation and precession have to do with each other?

19. Moving to Stations You will move to the station depending on the letter you were given during class When Mr. Houtz says go, you will move to your station quickly and read the directions. You will stay at your station and only at your station There are extra materials at the very front if you are interested If you finish early, you should answer the questions in full sentences in your notebook.

20. Stations Questions to answer while you work: 1.Why does the Earth experience precession? 2.Why does the Earth experience nutation? 3.What do nutation and precession have to do with each other?

21. Video https://www.youtube.com/watch?v=0qHjtp4cdCA https://www.youtube.com/watch?v=Dw4Xhw4q4ec https://www.youtube.com/watch?v=qNO-BPzPxPk https://www.youtube.com/watch?v=lkWyM-M8o0c

22. Hands On https://www.youtube.com/watch?v=cquvA_ IpEsA https://www.youtube.com/watch?v=cquvA_ IpEsA

23. Get back to original groups, put all notes away

24. Progress Reports – All grades are --/100% on EVERY assignment – Grades that are blank do not count against your grade (but they will soon!) – Grades that are blank with a * next to the name will never count (excused) – Grades that are 0 are missing – Homework is broken down by 100, 85, 70, or 50% – If you have a dispute, make note on your progress report and return it to Mr. Houtz

25. Exit Ticket Ready?Questions?Comments?

26. 1. Draw the shape of Earth’s orbit around the sun. 2. Explain why Earth takes the path you drew in question #1. 3. What is the angle of the Earth’s tilt on its axis? 4. Explain what Kepler’s laws tells us. 5. Explain how Earth moves about the solar system (be sure to use rotate, revolve, nutation, precession in your response).