the primordial earth hadean and archean eons solar system includes: sun planets moons asteroids...
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THE PRIMORDIAL EARTHHadean and Archean Eons
Terrestrial or Inner Planets
Earth
Small Dense (4 - 5.5 g/cm3) Rocky and include Metals
Diameter ± 13,000 km (8000 mi) Oceans cover > 71% of surface Atmosphere:
78% nitrogen 21% oxygen
Average density = 5.5 g/cm3
Crust density = 2.5 - 3.0 g/cm3
Core is densestMantle surrounds core. Surface temperature ranges
between roughly -50 and +60 °C.
THE PRIMORDIAL EARTHHadean and Archean Eons
THE PRIMORDIAL EARTHHadean and Archean Eons
Asteroid Belt
Between Mars and Jupiter
Likely a broken up planet orplanetesimal
THE PRIMORDIAL EARTHHadean and Archean Eons
Jovian or Outer Planets
Jupiter
Large Low density (0.7 - 1.5 g/cm3) Gaseous
THE PRIMORDIAL EARTHHadean and Archean Eons
Sun
The Sun is a star
Composition70% hydrogen 27% helium3% heavier elements
Temperature>20,000,000 ºC at interior
Energy comes from fusion of Hydrogen to form Helium
THE PRIMORDIAL EARTHHadean and Archean Eons
Sun
Sun's energy is the force behind many geologic processes on Earth:
Evaporation of water to produce clouds which causes precipitation which causes erosion
Uneven heating of the Earth's atmosphere causes winds and ocean currents
Variations in heat from sun may trigger continental glaciations
Sun and moon influence tides
THE PRIMORDIAL EARTHHadean and Archean Eons
Moon
The Moon is a satellite
Diameter ± 1700 km Density ± 3.3 g/cm3 Rotates on its axis at same rate as
it revolves around Earth, which results in same side of Moon always facing Earth.
Far side of moon is more densely cratered Dominant rock type is anorthosite
(related to gabbro)
Geology of the Moon
Lunar highlands Light-colored Rough topography Highly cratered More than 4.2 billion years old (Hadean in age)
Maria (once thought to be seas) Singular = Mare, plural= Maria
Large, dark areas Covered with basaltic lava flows Age of basalt is 3.8 to 3.2 billion years
THE PRIMORDIAL EARTHHadean and Archean Eons
THE PRIMORDIAL EARTHHadean and Archean EonsOrigin of the Moon
Moon may have formed as a result of an impact of another body with Earth about 4.4 billion years ago.
Debris from the impact thrown into orbit around Earth and aggregated to form the Moon.
THE PRIMORDIAL EARTHHadean and Archean EonOrigin of the Moon
Heat from impacts led to melting and differentiation (or segregation of materials of different density; low density materials rose and high density materials sank). 1. Low density alumino-silicates rose to surface to
form a crust 2. Higher density iron-rich minerals sank to form
the lunar mantle, and possibly a small core 3. Basaltic lava flows of the maria erupted following
large impacts somewhat later.
THE PRIMORDIAL EARTHHadean and Archean EonsOrigin of the Universe
Big Bang TheoryEvidence: 1. The galaxies are rapidly moving apart (Hubble's Law);
indicates that galaxies were closer together in the past (This was discovered in 1929 by Edwin P. Hubble; In 1914, W.M. Slipher first noted the red shift.)
Red shift:Light is shifted toward the red (or long wavelength) end of the spectrum.
Colors of the spectrum
R O Y G B I V 1. Red 2. Orange 3. Yellow 4. Green 5. Blue 6. Indigo
7. Violet
THE PRIMORDIAL EARTHHadean and Archean EonsOrigin of the Universe
Red = long wavelengthsBlue = short wavelengths Microwaves and radio waves are longer than visible Ultraviolet and X-rays are shorter than visible.
THE PRIMORDIAL EARTHHadean and Archean EonsOrigin of the Universe
The spectrum of a star reveals: •The star's composition (by means of absorption
lines; various elements in the star's atmosphere absorb parts of the light of the spectrum) and
•Whether it is moving toward or away from the Earth (and at what speed).
THE PRIMORDIAL EARTHHadean and Archean EonsOrigin of the Universe
Light reaching us from distant receding galaxies has its absorption lines shifted toward the red end of the spectrum.
This indicates that the galaxy is moving away from the Earth.
So, the red shift indicates that the universe is expanding.
A similar phenomen, except related to sound, is the Doppler Effect.
THE PRIMORDIAL EARTHHadean and Archean EonsOrigin of the Universe
THE PRIMORDIAL EARTHHadean and Archean EonsOrigin of the Universe
Big Bang TheoryEvidence: 2. Observed temperature of the universe today
(background microwave radiation) 3 degrees above absolute zero
THE PRIMORDIAL EARTHHadean and Archean EonsOrigin of the Universe
Big Bang TheoryEvidence: 3. Present abundances
of hydrogen and helium.
THE PRIMORDIAL EARTHHadean and Archean Eons
THE PRIMORDIAL EARTHHadean and Archean EonsFormation of the Solar System
The Solar Nebula Hypothesis