1. CH 15 SEC 5

2. GOAL/PURPOSE YOU LEARNED THAT GALAXIES ARE CLUSTERS OF BILLIONS OF STARS YOU WILL NOW LEARN THE ROLE OF GRAVITY IN FORMING AND MAINTAINING THE SHAPE OF OUR SOLAR SYSTEM YOU WILL ALSO LEARN ABOUT THE BIG BANG THEORY AND HOW THE UNIVERSE HAS CHANGED OVER TIME

3. THE BIG BANG BIG BANG- THE PERIOD WHEN THE UNIVERSE BEGAN. KEY- ACCORDING TO THE BIG BANG THEORY, THE UNIVERSE FORMED IN AN INSTANT BILLIONS OF YEARS AGO, IN AN ENORMOUS EXPLOSION. KEY- SINCE THE BIG BANG, THE SIZE OF THE UNIVERSE HAS BEEN INCREASING RAPIDLY AND IS BILLIONS OF TIMES LARGER THAN IT WAS IN IT’S EARLY HISTORY

4. HUBBLE KEY- IN THE 1920’S AN AMERICAN ASTRONOMER, EDWIN HUBBLE, HELPED DEVELOP THE BIG BANG THEORY HUBBLE’S LAW- STATES THAT THE FARTHER AWAY A GALAXY IS, THE FASTER IT IS MOVING AWAY FROM US. KEY- THE HUBBLE TELESCOPE WAS NAMED AFTER HIM

5. https://www.google.com/search?q =HUBBLE+TE&client=firefox- a&hs=p0U&rls=org.mozilla:en- US:official&source=lnms&tbm=isch &sa=X&ei=_3nmUrLJA8fZoATd1YH 4Dw&ved=0CAkQ_AUoAQ&biw=10 67&bih=433&dpr=1.5

6. EXPANDING KEY- THE UNIVERSE IS EXPANDING LIKE RISING BREAD DOUGH KEY- BASED ON CAREFUL MEASUREMENTS OF HOW FAST DISTANT GALAXIES ARE MOVING AWAY FROM US AND THE COSMIC BACKGROUND RADIATION, ASTRONOMERS ESTIMATE THAT THE UNIVERSE IS ABOUT 13.7 BILLION YEARS OLD

7. FORMATION OF SOLAR SYSTEM 1. A CLOUD OF GAS AND DUST FORMED A SPINNING DISC 2. GAS IN THE CENTER OF THE DISC COLLAPSED TO FORM THE SUN 3. THE REMAINING GAS AND DUST FORMED THE PLANETS 4. THE SOLAR SYSTEM INCLUDES THE SUN, PLANETS, AND BELTS OF ROCK, ICE AND DUST

8. http://www.brainpop.com/science/space/

9. Milky Way Spiral Galaxy

10. THE FUTURE KEY- NEW INFORMATION AND OBSERVATIONS LEAD MANY ASTRONOMERS TO CONCLUDE THAT THE UNIVERSE WILL LIKELY EXPAND …………………………………. http://www.youtube.com/watch?v=r0H6R7xRytk FOOOOOOORRRRRRRRRREEEEEEEEEEEEEEEEEV VVVVVVVVVVVVVVVVEEEEEEEEEEEEEEEEEEEER RRRRRRRRRRRRRRRRRRRRRRRRRRRRR

11. DARK MATTER AND ENERGY DARK MATTER- IS THE MATTER THAT DOES NOT GIVE OFF ANY ELECTROMAGNETIC RADIATION. KEY- DARK MATTER CANNOT BE DETECTED DIRECTLY. KEY- ITS PRESENCE CAN BE INFERRED BY OBSERVING THE EFFECT OF ITS GRAVITY ON VISIBLE OBJECTS SUCH AS STARS OR ON LIGHT. DARK ENERGY- IS CAUSING THE UNIVERSE EXPANSION TO ACCELERATE KEY- MOST ASTRONOMERS THINK THAT THE UNIVERSE IS MADE UP OF MOSTLY DARK MATTER AND ENERGY

12. http://www.brainpop.com/science/space/darkmatter/

13. CHECK FOR UNDERSTANDING WRITE THE Q & A WHAT IS THE BIG BANG THEORY? WHEN DID THE BIG BANG OCCUR? WHAT EVIDENCE IS THERE TO SUPPORT THE THEORY? HOW OLD IS THE SOLAR SYSTEM? WHAT IS DARK MATTER? WHAT EVIDENCE HAS LED SCIENTIST TO PREDICT THAT THE UNIVERSE WILL EXPAND FOOOOOORRRREEEEEEEVERRRR?