From Big Bang to Big Burp

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From Big Bang to Big Burp
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This Island Earth
About 4.5 billion years old
Geologically dynamic internally and externally
Only planet presently known to support life
As far as life is concerned Goldilocks of the
Solar System (relative to Sun, not too far, not
too close, just right !)
A closed system !
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Earth As A Closed System
Closed system exchange of energy but negligible
exchange of mass with surroundings
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The Earths Four Spheres
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How It All Began Or At Least How We Think It
Began O.k. its a good guess
Egg of energy
The Big Bang splattered radiation in all
directions
Expansion and cooling atomic particles formed
through conversion of energy to mass. E mc2
(energy mass x speed of light 2 )
Simple elements (hydrogen, then helium) fused to
form first stars
Heavier elements produced within giant pressure
cookers (stars)
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Formation of Galaxies
Stars and galaxies condensed out of the matter
produced by the Big Bang and continued to move
away from the point of the explosion. This is
still occurring.
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Redistribution of heavy elements
Dispersion of heavy elements into space results
from explosion (supernova) of stars
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Solar Nebula Hypothesis
Clumps of gas and dust accumulated, forming
large, irregular, nebulae clouds. Our solar
system is believed to have originated in one
such cloud.
Dust and gases settled gravitationally toward
mid-plane of slowly rotating disc.
After some of the matter had collected in centre
of disc, nuclear reactions began, forming Sun
Remaining gas and dust, moving in circular bands
around Sun collided and accreted to form
planets.
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Solar Nebula and Formation of Solar System
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The Nine Planets
Pluto
Neptune
Uranus
Saturn
Jovian planets
Jupiter
Mars
Earth
terrestrial planets
Venus
Mercury
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Early Evolution of Earth
Heating, partial melting of Earth due
to Impacting of extraterrestrial objects
(meteorites) Radioactive decay of unstable
elements Gravitational migration (sinking) of
heavy elements
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Jovian Planet Interior Jupiter
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Comparison of Terrestrial and Jovian
Atmospheres
Jupiter Major Hydrogen (81 ) Helium (18
) Minor Methane and other hydrocarbons Ammonia
Phosphorus Water Vapour
Venus Major Carbon Dioxide (96.5 ) Nitrogen
(3.5 ) Minor Sulphur Dioxide (0.015
) Water Argon Carbon Monoxide Helium Oxygen
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Comparison of Atmospheres Venus vs. Earth
Earth Major Nitrogen (78 ) Oxygen (21
) Argon (0.9 ) Water Vapour (0.05 to 2
) Minor Carbon Dioxide (0.03
) Methane, Ozone Rare Inert Gases
Venus Major Carbon Dioxide (96.5 ) Nitrogen
(3.5 ) Minor Sulphur Dioxide (0.015
) Water Argon Carbon Monoxide Helium Oxygen
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Evolution of Earths Atmosphere

• Initial atmosphere much like Jupiter
• (rich in Hydrogen and Helium derived from solar
  nebula)
• - burned off by Solar Wind
• 2. Second atmosphere much like Venus
• (dominated by Carbon Dioxide from Earths
  interior)
• - The Big Burp
• 3. Third and present atmosphere
• (rich in Oxygen)
• - modified from second atmosphere due to
• rise of anaerobic organisms

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Evidence of Bombardment by Other Objects
Obliquity of Axis
Uranus tipped on its side
Venus overturned
All planets have at least some tilt