1. Nebula Charged ion stream Blew lighter gases to the outer solar system Provides evidence that they were formed at the same time as the Solar Nebula Light Year AU (Astronomical Unit) Par-sec The Sun (a star) The Sun (a star) The Planets The Planets Moons Moons Asteroids Asteroids Comets Comets

2. Inner = Heavy elements, Rocky “Terrestrial” Outer= Lighter elements, Volatile “Gas Giants” Nearby supernova began the collapse of the Solar Nebula 4.6 Billion Years Asteroids Moon Rocks Hydrogen Helium Heavy elements from exploding stars Radiometric Dating- Absolute Age Relative Dating- Comparison Age

3. Layers from High to Low Density: Core, Mantle, Crust GasesDebris Dust Grains Fossils & Banded Iron Formations in Rocks Heat left over from the formation of the Earth (Primordial) Radioactive Decay NO! There was no OXYGEN just gases Similar to volcanic

4. Radar- using the Doppler Effect Planet Planet Stars Stars Galaxies Galaxies Inverse Square Law of Light Planets appear to Move compared to a stationary background of stars Parallax

5. Nuclear Fusion- light Element fused to heavier elements Hydrogen is fused to Helium (+ other heavy elements) Hydrogen Spectral Analysis Spectral Analysis Analyze the light Analyze the light from stars from stars The elements The elements present present The abundance of The abundance of elements present elements present

6. May have caused mass extinction 65 mya (dinosaurs + others) Cretaceous-Tertiary or K-T Extinction Evidence found on the Moon, Mercury, & other Solar System bodies Asteroids Active recycling (erosion) Has erased evidence of Impact craters on Earth

7. Gas, Dust, & Billions of Stars - 100,000 ly across - 10,000 ly thick The Milky Way Galaxy Outer Edge of the disk in a spiral arm Gravity

8. Stars→galaxies→Groups(few)→ Clusters(thousands) →superclusters Stars The Gravitational effect it has on visible matter -Position in the sky (Coordinates) -Brightness -Elemental Composition Dark Matter Almost 90%

9. -Hydrogen-Helium-Lithium SupernovaExplosions (massive stars only) They have: High Temperature High Velocity In our Sun & most Stars Nucleosynthesis

10. Spectrum SurfaceTemperatureLuminosity Luminosity Telescopes using all wavelengths of light Size, Color, Chemical Composition, Surface Gravity, Temperature, Age (stage of their life Cycle)