1. Astronomy Earth in Space astro.washington.edu

2. Key Vocabulary Aphelion Axis Barycenter Big Bang ellipse Galaxy cluster Local cluster Milky Way galaxy Nuclear fusion Nutation Perihelion Precession Revolution Rotation Solar System summer solstice vernal equinox winter solstice *compare *contrast *describe

3. What do you know about the universe? http://www.youtube.com/watch?v=Zr7wNQw12l8 http://www.youtube.com/watch?v=7_2Ts0JpB-M Each team has been given a sheet of 3 truths. Decide which is a lie(not the truth). Watch the video closely to determine which is a lie.

4. The Universe Houses all existence Is growing larger Contains billions of galaxies http://www.esa.int/esaKIDSen/SEMX4EBE8JG_Our Universe_0.html http://www.esa.int/esaKIDSen/SEMX4EBE8JG_Our Universe_0.html From the largest to the smallest: Universe -> galaxy clusters -> galaxies -> stars with planets (solar systems) or stars (without planets) -> individual planets (like Earth)

5. Galactic Address Universe -> galaxy clusters -> galaxies -> stars with planets or stars (without planets) -> individual planets (like Earth) Universe  Local Group (28 galaxies)  Milky Way galaxy  Solar System  Earth

6. Size Representations Galaxy Cluster Individual Galaxy

7. The Milky Way Galaxy -Where we live I have at least 3 spiral arms. My center is about 100,000 light years wide. I am a spiral galaxy

8. Star Systems and Individual Stars Star with a solar system -the star looks different here because you are zoomed out to see the planets Star (Hubble Telescope) -close ups of individual stars

9. Our Solar System

10. Earth

11. Quick Check 1 1.What galaxy do you live in? 2.What is the name of the star that accompanies our solar system? 3.Do all stars have planets? 4.When galaxies are grouped together, what do they form?

12. How did the universe form? Big Bang Theory Read p. 720 As your read: answer 1.How long ago did the universe form according to the Big Bang? 2.What direction did matter move? 3.What was created when the dense, hot, super massive ball exploded?(2 things) 4.Visual: How long after the universe began did the first stars and galaxies begin to form? 5.Honors: Name 2 types of evidence used to support the theory. http://www.esa.int/esaKIDSen/SEMSZ5W JD1E_OurUniverse_0.html http://www.geekologie.com/2009/08/int eresting-video-explaining-t.phpp What happened? We are moving away rom each other!

13. Big Bang Super hot, massive dense ball  its material began to move outward in all directions  universe began  universe began to cool  atoms formed  stars and galaxies formed  they continue to move outward No new atoms have formed since this time. Talk about recycling!

14. Balloon Lab Make sure you complete the task and answer the questions! Answers must be turned in to the basket on the blue book shelf!

15. Will the universe keep on growing? Open Universe It depends on its average density: it just may continue to grow forever Scientists currently believe this will happen! Big Crunch Will occur if average density gets to high Galaxies will begin to move outward less quickly until they stop A gravitational contraction would occur The galaxies would collide and form a high density mass

16. Compare and Contrast the Big Bang and the Big Crunch using a Venn- Diagram

17. Solar System Formation: Nebular Hypothesis Rotating cloud of gas(hydrogen and helium) and dust called the nebula  collapses into the center  heat is generated  protosun formed  nuclear fusion began  sun formed  nebula began to cool and solids form  solids make rings  particles in rings collide forming planets Heavier materials made 4 inner planets, lighter materials and gases made 4 outer planets

18. Nebular Hypothesis Our solar system formed about 4.6 billion years ago Temperature of the collapsed center reached 10 million degrees Kelvin – Nuclear fusion began Fuels the star (mainly when hydrogen atoms fuse to make helium atoms) Center of atoms combine to make a larger one(creates a new element) Fusion releases a lot of energy Read page 3,4,5

19. Earth: A Unique Planet A.Earth’s Shape 1. appears to be a perfect sphere from outer space 2. circumference(distance around) varies a. 40 007km around the poles b. 40 074 around the equator *equator = an imaginary line that divides the earth into Southern and Northern Hemispheres 3. Oblate spheroid(slightly flattened sphere) 40074 km 40007km A person would not have to have as much gas to travel around the poles (if they were able to drive the same type of vehicle.

20. Earth’s Gravity Gravity is the force of attraction that exists between all matter in the universe The amount of the force depends on the mass of the objects and the distance between them larger the mass of 2 objects, the closer together they are = greater force of gravity Causes Earth to go around the sun Causes the sun to be pulled towards the center of the Milky Way Galaxy - greenstonepatent.com scienceuniverse101.blogspot.com

21. Barycentre(barycenter) Barycentre: the center of mass or the point between 2 objects where they balance each other – In our solar system: Planet and the sun orbit around the center of the mass(BabyCenter) – http://spaceplace.nasa.gov/bar ycenter/ http://spaceplace.nasa.gov/bar ycenter/ – Used for planet hunting: when a star and a planet have a common barycentre the star wobbles; thus, a wobbling star indicates a planet www.youtube.com/watch?v=CnLwLF4e6uQ

22. Kepler's First Law of Motion Describes shape A planet does not travel around the sun in a perfect circle; it travels in an oval shaped pattern called an ellipse(sometimes called an elliptical pathway) The sun is at one of the focus points; it is not directly in the center http://howthingsfly.si.edu/flight- dynamics/kepler%E2%80%99s-laws-orbital- motion I look like a flattened pancake! Earth is moving at a speed of 107 000km/hr

23. Kepler’s Second Law of Motion describes the speed at which any given planet will move while orbiting the sun The line joining the planet to the Sun sweeps out equal areas in equal intervals of time Speed of planet changes – Moves the fastest: closest to the sun – Moves the slowest: farther from the sun – http://www.physicsclassroom.c om/mmedia/circmot/ksl.cfm http://www.physicsclassroom.c om/mmedia/circmot/ksl.cfm

24. Kepler’s Third Law of Motion compares the orbital period and radius of orbit of a planet to those of other planets the period for a planet to orbit the Sun increases rapidly with the radius of its orbit It is a mathematical comparison!

25. Investigation: Gravity and Orbits Background: 1.A moving body tends to move in a straight line at constant speed unless some outside force acts on it. 2.Gravity is the outside force that acts on satellites and keeps them in orbit around the earth. 3.Earth orbits the sun in a counter clockwise motion. Earth rotates in a counterclockwise motion. Purpose: To model the effect of gravity on a moving body. Materials: bowl, bead, paper, pencil

26. Investigation: Gravity and Orbits 1. Place the bowl face down in the center of the paper and trace a circle around it. 2. Mark 4 points at equal distances around the circle. 3. Number the points 1,2,3,4. 4. Place the marble in the circle. Place the bowl upside down over it. 5. Slowly swirling bowl in a clockwise until the marble rolls smoothly along the rim of the bowl; get the bead spinning around the rim of the bowl. 6. Stop swirling the bowl as the marble approaches #1, then quickly lift the bowl, allowing the marble to escape. 7. Observe and record its path. Draw the entire pathway on your paper and label it #1. 8. Repeat 4-6 and stop at position 2. Draw the entire pathway on your paper and label it #2. 9. Repeat 4-6 and stop at position 3. Draw the entire pathway on your paper and label it #3. 10. Repeat 4-6 and stop at position 4. Draw the entire pathway on your paper and label it #4.

27. Investigation: Gravity and Orbits 1.---What path does the marble take when the hoop is removed? --- Is the pattern of the path the same for all exit points? 2. In what direction does the rim of the bowl push the marble? 3. What force does the rim of the bowl represent? 4. Compare the motion of the marble to that of a satellite around earth. Be sure to include how they are alike and how they are different.

28. Earth’s Motion: Rotation Earth spins around its imaginary axis in a counterclockwise direction Creates night and day --Solar day: 24 hours in time --Sidereal day : 23 hours 56 min and 4 sec Causes Coriolis effect(wind appears to be turned/deflected) Sun appears to rise in the east in the morning and sets in the west astro.cornell.edu

29. Earth’s Motion Revolution(orbit) defined as the motion of a body along a path around some point in space The movement of Earth in its orbit around the sun in an elliptical pathway – causes the sun to appear to be displaced about 1 degree daily – Perihelion: January 3: Earth is closest to the sun(147 million km) – Aphelion: July 4: Earth is farthest from the sun(152 million km) moon revolves around Earth snyder7hills. org

30. D. Precession 1. result of forces acting on a spinning body *gravitational force on rotating Earth by the moon, sun, other planets 2. causing earth’s axis to move in an ellipse(takes 26, 000 years) * Axis presently points towards Polaris in the year 14 000 it will point towards Vega Earth’s Motion: Precession oceanworld.tamu.edu

31. Earth’s Motion Note the direction of the tilt of Earth in the revolution of each picture.

32. Earth’s Motion: Nutation E. Nutation = wobbling around the processional axis (This is a change in the angle—½ degree one way or the other.) 1. occurs over an 18 year period 2. due to the Moon exclusively. 3. very slightly increase or decrease the amount of seasonal effects

33. More Motion F. Earth moves with the solar system towards Vega at 20km/sec. G. Sun revolves around the galaxy 250 000 km/sec: 230 million year trip. H. Galaxies( group of stars, gas, dust held together by gravity) are moving outward. As their distance increases, their speed increases.