The Beginning of the Universe

1
The Beginning of the Universe

• Big Bang Theory
• Solar System

2
Reading from the Book

• Read Pages 774 778 an answer the Following
• Vocabulary
• Big Bang Theory
• Hubbles Law
• Cosmic Background Radiation
• Concepts
• When did the Big Bang occur?
• What evidence supports the Big Bang?How can
  astronomers infers how long the universe has been
  expanding?
• How long ago did the solar system form?
• What events led to the birth of the sun
• How did Planetesimals form Planets?

3
Big Bang Theory

• 13.7 Billion Year ago
• Universe formed in an instant explosion
• Cooled as it expanded
• Hubbles Law- the farther the galaxy, the faster
  it is moving away from us.
• Cosmic Background radiation
• Thermal energy left over from the Big Bang.
• Distributed in every direction as the universe
  expanded

4
Big Bang Theory

• 13.7 billion years ago
• Hundred thousand years after atoms
• 200 million years after big bang first stars
  and Galaxies
• About 5 billion years ago the solar system formed.

5
Solar System formation

• 5 billion years ago
• Giant Cloud of gas and Dust (Solar Nebula)
  collapsed to form the solar system
• Gravity pulled the solar nebula together
• Fast spinning and flattened to form a disk
• Sun formation
• Gravity pulled gas to center of disk
• Gas became hot and dense for nuclear fusion

6
Solar System formation

• Outer parts of the disk
• Gas and dust formed asteriod bodies
  planetesimals
• Planetesimasl crashed and stuck together becoming
  bigger until planets were formed
• Heat made inner planets rocky and small
• Outer part of disk
• Outer planets Captured hydrogen and helium from
  space
• More gravity and Bigger
• Jupiter Uranus, Saturn and Neptune
• Farther from center Huge disk of Ice and other
  substances