History of the Earth Chapter 1 Formation of the Earth Origins of�

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					History of the Earth Chapter 1:
    Formation of the Earth




                  From the Big Bang to Early Planets




    Origins of…
•   The Universe (13.7 Gyr)
•   The Elements (13.7 - 4.6 Gyr)
•   The Solar System & the Earth (4.6 Gyr)
•   The Moon (4.5-4.6 Gyr)
Origin of the Universe (13.7 Gyr)



  The
Big Bang



  Quantum Mechanical Statistical Vacuum Fluctuation?




                        Hubble Deep Field
Electromagnetic Radiation




       Evidence:
     Doppler Effect
   Electromagnetic Radiation




Red Shift
   &
Blue Shift
 Red Shift of
  Spectrum




              Galaxy Velocity
                   Galaxies
far




near             More Red Shifted
       slow                         fast

                Hubble law
  Expansion
    of the
   Universe




The galaxies are not moving through space, they are stationary is
space. Space itself, between the galaxies is stretching and carrying
the galaxies farther away from each other.




            History of the Universe
                   WMAP
         Wilkinson Microwave Anisotrophy Probe




Microwave light emitted 380,000 yrs after the Big Bang




   Stars Begin to Form about
300,000 years after the Big Bang




                                     At that time Universe is:
                                     • 75% Hydrogen
                                     • 25% Helium

       What about the rest of the elements?
Nebula
How a Star Works




         Radiation   Gravity
         Pressure




 Nucleosynthesis
Stellar Death: Collapse




            Radiation     Gravity
            Pressure




Supernova: Crab Nebula
                                  Supernova
                                  Remnants




         Origin of the Elements

• Hydrogen & Helium: Big Bang

• Helium to Iron: Stellar Fusion
     Multiples of 4 most common:
      Helium Carbon, Oxygen, Neon, Magnesium,
      Silicon, Sulfur, Iron

• Iron to Uranium: Supernova
 Origin of the Solar System:
          The Data




1. 99% of the mass of the solar
     system is in the sun
      2. We know the
   composition of the sun




3. Planets orbit the sun in the
  plane of the sun’s equator
     4. Planets come in two groups:
           Terrestrial Planets
           - Small, Dense and made of Rock and Iron

Mercury         Venus                 Earth               Mars




     4. Planets come in two groups:
             Jovian Planets
          - Large, Low Density, and Made of Gas and Ice



      Jupiter               Saturn
                                              Uranus      Neptune
                         Asteroids


Mathilde & Eros (NEAR)

     Ida & Dactyl




           Kuiper Belt & Pluto
               5. Meteorites




                Chondrites



                               Ordinary




Carbonaceous
      Chondrules under a scope




                          X-Ray Image




Abundance of
 Elements in
Carbonaceous
 Chondrites
 Achondrite - Stony Meterorite




A stone from the Stannern eucrite shower
that fell over Moravia, Czech Republic in 1808.




   Iron
  Meteorite
                              Stony-Iron:
                                Palasite
                    Olivine




Iron




       6. Properties of the Earth
Origin of the Solar System:
       Interpretation
 Solar Nebula Hypothesis




        1. Start With a Nebula


                               Something
                              (Supernova?)
                                Triggers
                                Nebula to
                                Collapse
Eagle
Nebula
2. Nebula Collapses to form
    Protostar (Early Sun)
                  Protostar
                 Formation



3. Residual Material Begins to
      Cool and Accrete
3a. “Gas” Segregated by Melting
  Temperature and Condenses




 3b. Accretion: Dust Particles
  Accrete into Planetesimals
3b. Planetesimals Accrete into
           Planets




  DaDa! - A Solar System
Dust Disks
 Around
 Young
  Stars
   Extrasolar
    Planets




 First Extra-
 Solar Planet
Photographed
   (2005)
  4. Terrestrial
 Planets Heat up
and Differentiate:
Iron Catastrophe
Heat Comes From:
1. Kinetic Energy of Accretion
2. Gravitational Energy
3. Radioactive Decay
4. Differentiation




                                 Earth’s
                                 Interior
            Meteorite Sources




 Meteorites & Solar System Age
•Formation: 4.56 billion years
      Meteorites all with 20 myrs
      (earliest within few Myrs of supernova)
•Supernova to sun and planetesimals - few million years!
•Layered earth about 96±12 Myrs after meteorites
•Nebula to layered earth & moon - about 100 Myrs
Earth in the Early Hadean?




      2004 - Fred Sulahria