Formation of the Universe

• Cosmology


  The science of the origin and development of the universe
• In the last 100 years, technologies have been developed that help scientists find evidence for cosmological theories
• There were and are still many unanswered theories because space technology was not developed until recently. Until the 1920s, astronomers thought that the Milky Way was the entire Universe!
• Questions Related to Cosmology

  • How was the universe formed?
  • What was responsible for forming the universe?
  • What existed before the universe?
  • What will happen to the universe in the future?
• Big Bang Theory


  All matter and energy in the Universe expanded from a single point
• Estimated to have occurred between 13.6-13.8 billions years ago
• Formation of the Universe

  1. At the first instant of time and space, the Universe was very hot, and energy was spreading outward very quickly

  2. The Universe slowly cooled and energy slowly began turning into matter – mainly hydrogen

  3. Over hundred of millions of years, the matter formed clumps which eventually formed the celestial objects we have in the Universe
• Dark Matter


  Matter that exists in space that has gravity, but cannot be seen. Function: Brings galaxies together.
• Dark Energy


  Repulsive force that works against the force of gravity. Function: Causes the universe to continue to expand indefinitely.
• Both dark matter and dark energy are theoretical as they have never been detected
• Scientists can only make inferences about dark matter and dark energy from its effects on the space and matter we can see
• The universe is currently expanding
• Red Shift


  Galaxies shift toward the red end of the visible spectrum when they are moving away from the Earth
• Hubble's Law states that the farther away the galaxy, the greater the red shift, and, therefore, the faster it was moving away from Earth
• A star speeding away from you emits longer wavelengths of light, which appear redder
• Scientists use spectroscopy to observe the red shift in visible light and other radiation emitted from distant galaxies

  
• Hubble's law allowed astronomers to calculate how long ago galaxies started moving apart, which provides an estimate of when the Big Bang occurred and how old the Universe is, and to prove that the Universe is constantly expanding
• Astronomers have discovered that the effect of dark energy was being felt 9 billion years ago and has steadily increased over time
• Over the course of the next billions of years, dark energy will continue to grow stronger, eventually pulling apart galaxies and leaving the Universe filled with even more cold, empty space