Formation of the Universe

• Light year - The distance light travels in a year.
• Earth

  • 71% ocean
  • Also called the "Blue Planet"
• Our Solar system is formed from a vast, rotating cluds of gas and dust called super nebula.

  Each part of the nebula exerted a gravitational attraction on other the other parts, which tended to make the nebula contract.
• A nebula is a giant cloud of dust and gas in space. Some nebulae (more than one nebula) come from the gas and dust thrown out by the explosion of a dying star, such as a supernova. Other nebulae are regions where new stars are beginning to form called star nurseries
• Helix Nebula - closest nebula to the Earth
• Normal matter

  • Ordinary matter
  • Consisting of protons, electronics, and neutrons that comprise atoms and planet stars, galaxies, and other bodies
  • 4-5% of the universe
• Dark Matter

  • Matter that has gravity but does not emit light
  • 25% of the universe
• Dark Energy

  • A source of anti-gravity; a force that counteracts gravity and causes the universe to expand.
  • 70% of the universe.
• Speed of light - is a fundamental physical constant, the speed which light and all electromagnetic radiation travel in a perfect vacuum.

  THe speed of light in vacuum is 186,282 miles per second (299,792 kilometers per second)

  Nothing can faster than light, you could go around Earth 7.5 times in one second
• Protostar - an early stage in the formation of a star resulting form gravitational collapse of gases.
• Thermonuclear reaction - a nuclear fusion reaction responsible for the energy produced by stars.
• Main sequence stars - stars that fuse hydrogen and atoms to form heluim atoms in their cores; outward pressure resulting from nuclear fusion is balanced by gravitational forces.