The Universe

• Is the cosmological model of universe that is best supported by all lines of scientific evidence and observations


  Big Bang theory
• About how many years ago at tremendous explosion started the expansion of the universe

  About 15 billion years ago
• Belgian catholic priest cosmologist and scientists who proposed the big bang theory of the origin of the universe

  Georges Lemaitre
• When was the big bang theory proposed by georges

  1927
• One of the scenarios predicted by scientist in which the universe may end


  Big Crunch Theory
• Big crunch theory is based on what theory

  Einstein's theory of general relativity
• Theories about the origin of solar system

  Dynamic encounter theory planetesimal theory exploding star theory planetary nebular theory
• The theory that proposes the historical origin of the solar system as a result of the collision of sun and a comet

  Dynamic encounter theory
• Who proposed the dynamic encounter theory

  Georges leclerc and comte de buffon
• A collision encountered theory proposes that a star actually get closed and collide with the sun, then turned into planetesimals

  Planetesimal theory
• A theory where in scientists have suspected a star explosion called supernova help trigger our solar systems formation


  Exploding star theory
• It is the most generally accepted evolutionary model for formation of the solar system from a cloud of gas and dust particles known as nebula


  Planetary nebular theory
• Relatively small, solid body of frozen water, methane, carbon dioxide and ammonia along with the dusty and rocky bits of materials mixed in

  Comets
• Comets became known to be as

  Dirty snowball
• The term dirty snowball was coined by


  Fred whipple
• These are the brilliant and most rare objects in the night sky

  Comets
• Who proposed the dynamic encounter theory

  Georgia's leclerc and comte de buffon
• Who proposed the planetesimal theory?

  T.C. Chamberlain and F.R. Moulton
• Where do comets came from?

  Comets came from the Oort cloud and Kuiper belt
• A spherical cloud of objects beyond the orbit of pluto from about 30,000 au

  Oort cloud
• How many comets are believed to be in the Oort cloud

  1 trillion comets
• Source of long period comets which orbital periods of more than 200 years


  Oort cloud
• A disc shaped region of small icy bodies which ranges 30 to 100 au from the sun


  Kuiper belt
• Source of short period comets which orbital periods of less than 200 years


  Kuiper belt
• Parts of a comet

  Nucleus, coma, dust tail, ion tail and head of a comet
• Made of rock iron dust and a variety of frozen chemicals including water and gases like carbon dioxide nitrogen carbon monoxide ammonia and methane

  Nucleus
• Can remain in a solid preston state an observed by even the world's most powerful telescope until it approaches a sun

  Nucleus
• Is the body of the comet

  Nucleus
• Large lazy head around a comet


  Coma
• Expelled water does gas and debris from a fuzzy haze around the nucleus as nucleus get cold and eventually warm as it approaches to the sun

  Coma
• Formed due to the vaporization of ices from the heavier debris and particles

  Dust tail
• Primarily affected by the comet's orbital path which means distal curves behind the nucleus as it orbits the sun, it is the movement of the comet

  Dust tail
• Formed when ionized gas are pushed directly away from the sun by the sun's high speed solar wind

  Ion tail
• Is the color of the comet

  Ion tail
• Colors of a comet

  White, yellowish, blue
• Formed when coma and the nucleus fused together

  Head of a comet
• A large cloud of invisible hydrogen gas surrounds the head and this hydrogen halo may be hundreds of thousands of kilometers across


  Head of a comet
• Examples of comets

  • Hale - bopp
  • Comet McNaught
  • Halley's comet
  • HyaKutake comet
  • Comet LoveJoy
• Remnants of asteroids and comets


  Meteoroids
• These are small rocky or metallic body traveling through space

  Meteoroids