1. BATTLE OF THE PLANETS
EARTH vs JUPITER

2. Small...
Rocky...
Liquid water...
Breathable Atmosphere...
Huge...
Gassy...
- 160o C...
...can you breathe
ammonia & methane?

3. solar nebular theory Nebula collapses due to gravity...
Forms spinning disk with protosun in middle...
Planetesimals form in disk...
Protoplanets develop; denser matter gathers closer to center, while less dense matter accretes in the periphery...
Fusion begins & blows away left-over dust & gas.

6. Inner & Outer planets
Inner planets contain large percentages of heavy elements (Fe, Ni).
Mercury, Venus, Earth & Mars.
Small, rocky dense.
Outer planets formed far away from sun (COLD!); kept their gases (H, He) and ices (methane, ammonia).
Jupiter, Saturn, Uranus, Neptune.
Large, gassy, low density.

7. Earth is...SO HOT!!!
HEAT from collisions (all those small planetesimals banging into each other.
HEAT from weight of layers piling on top of each other.
HEAT from decay of radioactive materials within Earth.

8. DIFFERENTIATION
HEAT caused early Earth materials to be in a molten state.
Dense material (Fe, Ni) sank towards center...
Less dense material (Si) winds on top.
Core...mantle...crust.

9. Atmosphere
Less dense gases (H, He) rise to top & become first Earth atmosphere; doesn’t last long (too light to be held by gravity).
OUTGASSING from volcano eruptions releases water vapor, CO2, N2, CH4, SO2, NH4 to form second atmosphere.
As life develops, organisms use CO2 during photosynthesis to arrive at present-day O2 atmosphere.

10. Where did all that water come from?

11. Maybe from outer space!
THEORY: Comets struck Earth, bringing ice/water to atmosphere.
Rain resulting from comet ice/water gave Earth the oceans.
Salt in oceans comes from land runoff.
...or maybe the water came from volcanoes...?

12. BATTLE OF THE PLANETS
(part II)
EARTH vs Mars

13. Year = 365 days
Mt Everest: 8 km high
Plenty of malls...
All your friends are here
Year = 687 days (you’d
only be 8 yrs old...)
Olympus Mons: 24 km
Possibility of H2O...