Earth Science

• Nebula - an interstellar gas cloud of ionized particles
• terrestrial planets are smaller than jovian planets according to the nebular theory because of the low abundance of metallic elements
• according to the nebular theory, supernova disrupted the stability of the nebula that resulted in the formation of the solar system
• the solar system originated from the nebula according to the nebular theory
• the jovian planets are composed of Jupiter, Saturn, Uranus, Neptune
• the particles that did not become planets in the solar system:

  • became a part of the oort cloud
  • became asteroids
  • becamethe debris in the kuiper belt
• the high melting point of metals and silicates enables the formation of solid, terrestrial planet
• the temperature increased as the nebula became denser due to increasing gravitational force
• terrestrial planets include Mercury, Venus, Earth, Mars - they were primary mate of silicate rocks and metals
• scientists that proposed the nebular theory are:

  • Immanuel Kant
  • Emanuel Swedenborg
  • Pierre Simon Laplace
• according to Georges Henri Joseph Edouard Lemaitre that the universe started from the sudden expansion of a primeval atom or "cosmic egg"
• supports the big bang theory

  • the wavelengths of light from galaxies moving away from Earth are redshifted
  • a small amount of heat is spread around the universe
• the cosmic background radiation prove that the universe began from a hot and violent expansion
• the CMBR is an important evidence of big bang theory. this radiation is believed to be the leftover of big bang. if this radiation is not present, the tempersature of the space of the universe is 0k
• the gravitational force dominated the universe during the big bang
• Arno Penzias and Robert Wilson discovered the cosmic microwave background radiation
• Penzias and Wilson discovered that microwaves with wavelengths of about 7 centimeters were present in space
• the Hubble's law describes the correlation of the velocities and distance
• big bang theory is a cosmological model explaining how the universe began
• the big bang theory started as a singularity
• according to the big bang theory, the singularity from which the universe had started expanded and decreased in temperature
• the scientist that considered as the first proponent of big bang theory is Georges Lemaitre
• water from the comet and water from the earth have the same isotopic composition
• the hydrosphere is composed oof 97.5% saltwater and it is also called as the saline water
• water served as a medium that dissolved molecules and enabled their chemical reactions
• water came from the comets collided with the earth
• hydro is the greek root word that means water
• the fresh water is available in form of groud water and it is 2.5% of the total water on Earth.
• if water cannot store heat from the sun, the conditions of the atmosphere during winter will be extremely cold and extremely hot during the summer
• examples of forms of water are steam and liquid water
• water has high heat capacity that largely affects the day-to-day weather conditions
• four major spheres of the Earth: Hydrosphere, Biosphere, geosphere, atmosphere
• James Lovelock proposed Gaia Hypothesis which postulates that the Earth works as a self-regulating system
• Lynn Margulis, an evolutionary theorist, further developed Lovelock's Gaia hypothesis
• NASA's Earth Science program study the Earth system through satellite for long term observation
• Alexander von Humboldt helped establish the foundation of ESS by recognizing patterns from collected specimens and measurements
• the proponent of Gaia hypothesis
• the concept of uniformitarianism states the the geological forces in the past are the same as those in the past
• four major spheres of the earth: Hydrosphere, Biosphere, Geosphere, and Atmosphere
• father of modern geology: James hutton