Tuesday, January 29, 2013

Origin of the Earth

  • Earth began as nothing more than a rock surrounded by lava 4.5 billion years ago
  • Ancient stars reached their end and exploded, leaving stardust that eventually collapsed because of gravity and formed the solar nebula
  • The planets were created from dust that went around the early sun and collided with each other due to gravity, causing them to stick together
  • Starting out as pebbles, they eventually formed into the four first planets: Mercury, Venus, Earth, and Mars
  • In the northwest corner of British Columbia, a meteor was discovered in a lake there which gave scientists clues to the beginning of the earth.
  • Age of meterorites are almost the same as the age of the earth.
  • Iron catastrophe was the global migration of the elements sinking down, forming a molten core 2 times the size of the moon
  • The magnetic north pole changes positions even today and it is believe that between 40-50 years from now it will be in Siberia
  • The core's magnetic field that surrounds the planet protects it from the harsh solar flares that the sun gives off
  •  Based on the rocks gathered during the Apollo mission, scientists discovered that the moon was millions of years younger than the Earth
  • There was one theory that the moon had collided into the Earth, making it larger, and some of the molten rock that were ejected from the impact got stuck in the Earth's orbit and formed to create the moon
  • Because the moon was closer, the Earth began to spin faster, making the day go by less than six hours
  • Once the moon had drifted away from it, the Earth slowed down and spins at the speed it does today
  • In Australia, zircon, an extremely rare crystal that is created when lava is cooled, was found there in the rocks there and radioactive dating showed that it the oldest was formed around 4.4 billion years ago
  • There was an idea that because volcanoes form steam, then, when the Earth cooled, there was a rain storm, and that is where the Earth's water came from
  • Another idea was that water came from ice bearing comets that hit the Earth
  • Half of the mass of comets that had dust and ice was water
  • The comets' impacts possibly caused acidic rain
  • Comets are fickle and like cats; they both have tails and do what they like