1. High P and T at center of Solar nebula cause hydrogen atoms to fuse together to form helium Solid particles condense and collide to form planetesimals which accrete into planets Lindsley, 8/99

2. Solar system: outer jovian planets, inner terrestrial planets, Pluto the oddball Lindsley, 8/99

3. Jovian planets: Low densities Overall mass is large Thick atmospheres over small rocky cores Lindsley, 8/99

4. Terrestrial planets: Relatively small Relatively high densities Mostly rock with only a thin, or no, atmosphere Lindsley, 8/99

5. Basalt forms most of the surface area of terrestrial planets Lindsley, 8/99

6. Manicouagan Crater (Quebec) is evidence of meteorite impact. 210 m.y. old 75-100 km across Filled with a ring lake Lindsley, 8/99

7. Earth is unusual because it is rich in water and its crust (outermost layer) includes other rocks than basalt Lindsley, 8/99

8. Active plate tectonics causes earthquakes and volcanic eruptions, but also recycles oxygen and other biochemical necessities Lindsley, 8/99

9. Sand dunes, Namibia Lindsley, 8/99

10. Wind-deposited sandstone, Zion National Park, Utah Lindsley, 8/99