1. Our Solar System http://www.youtube.com/watch?v=pUZ2tfr1bsU

2. Essential Question Why is the solar system arranged the way it is? Why are the planets, asteroids, Kuiper ice objects.

3. Nebula )

4. Demo: 1.Obtain a water bottle with a cap. Fill it 2/3rds full of water. 2. Pour several pebbles and large gravel pieces into the bottle. 3. Obtain a ¼ of a piece of Alka-Seltzer. Quickly place it in the bottle and put the cap on tight. 4. Gently shake the bottle for several seconds then place it upright on the table.

5. Nebular Hypothesis of the Origin of the Solar System

6. Step 1. About 5 billion years ago Nebulae of gas (hydrogen and helium) and dust a light year across. Due to a nearby supernova explosion (?) it begins to contract As it contracts, it spins faster. Flattens into a disk shape

7. Step 2: The center contracts and heats up forming a proto-star. The Sun (99% of the mass) formed at the center Sorting: Heavier material (rock an metal) gravitate toward the center. Lighter gas and dust get blown farther out

8. Step 3: Repeated collisions caused the smaller pieces of solid material to collide and condense (combine) to form larger, rocky inner planets and asteroid belt.

9. Step 4: Within a few million years these bodies cooled, cleared their neighborhood and formed into the icy gassy outer planets, etc.

10. Exit Slip 1. How are the planets in the solar system sorted? 2. Which planets are more dense? define density:

11. Earth’s Early History Bombardment by high velocity meteorites and comets generated immense amounts of heat energy and melted the metals and rock on the young planet. The denser materials like iron (Fe) sank into the core of the Earth. lighter silicates (Si), oxygen (O) compounds, rise near the surface. decay of radioactive elements in the Earth, generate heat