1. March 19 & 20 Do Now – Take a clicker; set aside for end of class. Take a look at your ‘What The ?!’ Question sheet. Do Now – Take a clicker; set aside for end of class. Take a look at your ‘What The ?!’ Question sheet. Are there any questions you are able to answer? If so, answer them Are there any questions you are able to answer? If so, answer them Are there any questions you still have? If so, write them down Are there any questions you still have? If so, write them down HW– Prep for your open notes test on CH 9 through everything we’ve learned about universal gravitation HW– Prep for your open notes test on CH 9 through everything we’ve learned about universal gravitation Objectives– Scale of Universe Analogies; YouTube Videos, Assign 3 rd MP project, Review HW due today, test prep Objectives– Scale of Universe Analogies; YouTube Videos, Assign 3 rd MP project, Review HW due today, test prep

2. The TWO-INCH Universe A powerful set of analogies to examine size and distance in astronomy Source: smithsonianeducation.org

3. Earth’s diameter = 8,000 miles QUESTION: If Earth is just two inches wide, how big would the Moon be at this scale? QUESTION: If Earth is just two inches wide, how big would the Moon be at this scale?

4. Moon = ¼ inch! actual diameter = 2,000 miles actual diameter = 2,000 miles QUESTION: At this scale, how far apart should they be?

5. 5 feet! actual Earth-moon distance = 240,000 miles …1 light second! actual Earth-moon distance = 240,000 miles …1 light second! QUESTION: How big should the sun be in this analogy? QUESTION: How big should the sun be in this analogy?

6. A minivan (16 feet across)! Actual Sun diameter = 875,000 miles Actual Sun diameter = 875,000 miles QUESTION: If the 2-inch Earth were placed in the middle of the classroom, where would the minivan need to be parked to represent the position of the sun at this scale? QUESTION: If the 2-inch Earth were placed in the middle of the classroom, where would the minivan need to be parked to represent the position of the sun at this scale?

7. 6 football fields away! The van could be parked at The van could be parked at Robbinsville-Edinburg Road! Robbinsville-Edinburg Road! Actual Earth-Sun distance = 93,000,000 miles or 8 light minutes Actual Earth-Sun distance = 93,000,000 miles or 8 light minutes

8. NEW ANALOGY Scale down the minivan sun into a 2-inch sun Scale down the minivan sun into a 2-inch sun QUESTION: At this scale, how big would Earth be? QUESTION: At this scale, how big would Earth be?

9. A grain of salt! QUESTION: How big would the moon be? QUESTION: How big would the moon be?

10. A speck of dust! QUESTION: How far away would this “speck of dust” moon be from the “grain of salt Earth”? QUESTION: How far away would this “speck of dust” moon be from the “grain of salt Earth”?

11. ½ inch! QUESTION: How far away would the sun be from the “grain of salt” Earth? QUESTION: How far away would the sun be from the “grain of salt” Earth?

12. 20 feet!

13. New Analogy: 2-inch Solar System Sun speck in center, planets would be invisible at this scale! Sun speck in center, planets would be invisible at this scale! Actual solar system size = 7,000,000,000 miles (10 light-hours) Actual solar system size = 7,000,000,000 miles (10 light-hours)

14. Next nearest star at this scale (Proxima Centauri) would be 2 football fields away! Next nearest star at this scale (Proxima Centauri) would be 2 football fields away! Actual distance = 25.8 trillion miles or 4.3 LY Actual distance = 25.8 trillion miles or 4.3 LY Sun is 1 of billions of stars in our galaxy Sun is 1 of billions of stars in our galaxy QUESTION: At this scale, how big is the Milky Way? QUESTION: At this scale, how big is the Milky Way?

15. About the size of North America Actual Milky Way size = 100,000 LY Actual Milky Way size = 100,000 LY At this scale, if the tiny dot of light at the center of the solar system were a grain of salt, a teaspoon of the salt would represent about 100,000 of the Milky Way’s 200+billion stars! At this scale, if the tiny dot of light at the center of the solar system were a grain of salt, a teaspoon of the salt would represent about 100,000 of the Milky Way’s 200+billion stars!

16. New Analogy: The Realm of Galaxies Side note: Andromeda galaxy is a galaxy that is very near the Milky Way and is seen as a single smeary light to the naked eye Side note: Andromeda galaxy is a galaxy that is very near the Milky Way and is seen as a single smeary light to the naked eye Actual Andromeda size = 1.3 million trillion miles (220,000 LY) Actual Andromeda size = 1.3 million trillion miles (220,000 LY) Shrink the “continent-size Milky Way” down to 2- inches Shrink the “continent-size Milky Way” down to 2- inches QUESTION: If Milky Way is 2-inches big, what is the distance between these two galaxies? QUESTION: If Milky Way is 2-inches big, what is the distance between these two galaxies?

17. ~ 5 feet! Actual Milky Way-Andromeda distance = 15 million trillion miles (2.5 million LY) Actual Milky Way-Andromeda distance = 15 million trillion miles (2.5 million LY) At this scale, individual stars in these galaxies would not be visible even with a microscope At this scale, individual stars in these galaxies would not be visible even with a microscope At this scale, the deep space galaxies seen by Hubble would be 4 miles from this classroom! At this scale, the deep space galaxies seen by Hubble would be 4 miles from this classroom! So…QUESTION: How big is the universe? So…QUESTION: How big is the universe? Let’s watch: http://htwins.net/scale2/ Let’s watch: http://htwins.net/scale2/http://htwins.net/scale2/

18. YouTube Videos Take a handout and scan the questions NOW! You will be expected to answer them as we watch the videos as a class Take a handout and scan the questions NOW! You will be expected to answer them as we watch the videos as a class “Life Inside the Space Station” http://www.youtube.com/watch?v=nGefSuwGylg “Life Inside the Space Station” http://www.youtube.com/watch?v=nGefSuwGylg http://www.youtube.com/watch?v=nGefSuwGylg “NASA Zero-G Fun with the Vomit Comet KC-135 Reduced Gravity” http://www.youtube.com/watch?v=MMV_a7Olf2c “NASA Zero-G Fun with the Vomit Comet KC-135 Reduced Gravity” http://www.youtube.com/watch?v=MMV_a7Olf2chttp://www.youtube.com/watch?v=MMV_a7Olf2c “Space Toilet” http://www.youtube.com/watch?v=HUe2HcFUPSo&feature=relat ed “Space Toilet” http://www.youtube.com/watch?v=HUe2HcFUPSo&feature=relat ed http://www.youtube.com/watch?v=HUe2HcFUPSo&feature=relat ed http://www.youtube.com/watch?v=HUe2HcFUPSo&feature=relat ed “Hilarious G-Force training” http://www.youtube.com/watch?v=Yjg6mRFzZzE “Hilarious G-Force training” http://www.youtube.com/watch?v=Yjg6mRFzZzE http://www.youtube.com/watch?v=Yjg6mRFzZzE “Astronauts on the moon” http://www.youtube.com/watch?v=FAqjys-cxoU “Astronauts on the moon” http://www.youtube.com/watch?v=FAqjys-cxoU http://www.youtube.com/watch?v=FAqjys-cxoU

19. 3 rd Marking Period Project Take a rubric Take a rubric Change the 1 st bullet point to 100 points! Change the 1 st bullet point to 100 points! You will have ONE class period immediately following spring break to work on this. It is in your best interest to do some of the work over spring break. You will have ONE class period immediately following spring break to work on this. It is in your best interest to do some of the work over spring break. QUESTIONS? QUESTIONS?

20. HW Due today… Take out your HW and get your clickers ready Take out your HW and get your clickers ready Choose the answer that best corresponds with your answer. Choose the answer that best corresponds with your answer.

21. 21. Comment on whether or not this label is cause for concern… 1. Yes! Definitely cause for concern 2. Nope – not concerned 3. I have no clue what is going on Countdown 10

22. 22. Earth and moon are grav. attracted..… 1. The more massive Earth attracts moon w/ a greater force 2. The less massive moon attracts earth with a greater force 3. The forces are equal / the same

23. 23. Woman weighs 500 N; what is the grav. force on her? 1. More than 500 N away from Earth’s center 2. Less than 500 N away from Earth’s center 3. More than 500 N toward Earth’s center 4. Less than 500 N toward Earth’s center 5. 500 N toward Earth’s center 6. 500 N away from Earth’s center

24. 24. If gravity from sun on planets disappeared… ? 1. Planets would immediately stop moving and stay where ever they are 2. Planets would start moving straight towards sun and crash into it 3. Planets would take a tangent path Countdown 10

25. 25. Does the moon get 1.4 mm closer to the earth each second? Would it get closer if tangential velocity were reduced? … ? 1. Yes, yes 2. No, no 3. No, yes 4. Yes, no Countdown 10

26. 26. If the moon were 2x as massive, would force of earth on moon be 2x as large? Of moon on earth? 1. Yes, yes 2. No, no 3. No, yes 4. Yes, no Countdown 10

27. 29.Jupiter is 300x as massive as earth but you only weigh 2.5x as much (not 300x as much). Why? 1. Because Jupiter is more massive than Earth 2. Because Jupiter is less massive than Earth 3. Because Jupiter has a bigger radius than Earth 4. Because Jupiter has a smaller radius than Earth 5. No clue Countdown 10

28. 32.Earth’s mass and diameter both double – how does you weight change? A. ½ as much B. 2x as much C. ¼ as much D. 4x as much E. 1/8 as much F. 8x as much G. Weight stays the same Countdown 10

29. 33.On a ladder so you’re 2x as far from Earth’s center – how does your weight change? A. ½ as much B. 2x as much C. ¼ as much D. 4x as much E. 1/8 as much F. 8x as much G. Weight stays the same Countdown 10

30. 1A and 3A Take out HW due yesterday - we still need to finish reviewing a few questions Take out HW due yesterday - we still need to finish reviewing a few questions

31. 1A and 3A Take out HW due yesterday - we still need to finish reviewing a few questions Take out HW due yesterday - we still need to finish reviewing a few questions

32. From now until 3 minutes before the bell… Use this time to WISELY prep for your test. Use this time to WISELY prep for your test. Need more math practice? Need more math practice? See page 676 #1, 2, 4, 6 See page 676 #1, 2, 4, 6 See page 677 #1 & 2 at TOP of page See page 677 #1 & 2 at TOP of page Investigate any questions you still have from Do Now Investigate any questions you still have from Do Now Have questions? ASK NOW Have questions? ASK NOW Borrow Monster Note key if you still need to finish Borrow Monster Note key if you still need to finish Share your 2 websites with peers and use them to prep for test concepts Share your 2 websites with peers and use them to prep for test concepts When there are 3 minutes left – take an exit slip and complete; also please turn in your WHAT THE question sheet completed to the best of your ability! When there are 3 minutes left – take an exit slip and complete; also please turn in your WHAT THE question sheet completed to the best of your ability!