Galaxies & the Big Bang Theory PowerPoint Notes

Galaxies & the Big Bang Theory

Types of Galaxies

  •  Galaxies are made up of nebula, stars and black holes
  •  Three types of galaxies:

**Spiral
**elliptical--disk shaped
 **irregular--due to 2 
galaxies colliding?

Anatomy of a Galaxy

  •  There are 100 billion to a trillion stars in a galaxy
  •  Gravitational pull binds the galaxy together as stars revolved around the black hole in the center
  •  100-200 billion galaxies in our known universe


Milky Way Galaxy...Our Galaxy

Milky Way Galaxy

  •  Barred spiral galaxy
  •  100,000 light years in diameter

 Andromeda Galaxy is our sister galaxy

 Part of the Local Group: ~20 galaxies in our local group

Milky Way Galaxy

  •  All stars in the night sky are part of the Milky Way Galaxy
  •  The Milky Band in the night sky looks into the spiral arm
  •  The sun is about 2/3 the way out of the spiral arm


Big Bang Theory

  •  The theory of how the universe started 15-17 billion years ago from a large explosion
  •  H, He and Li formed during the Big Bang-- other elements due to nuclear fusion of stars


Supporting Evidence:

  •  Quasars: Very old galaxies that give off x-rays from their centers
  •  The Universe is still expanding: Doppler Effect: Galaxies are moving away from each other


Space Travel

  •  We will NEVER be able to travel across our galaxy.
  •  We can NEVER go the speed of light
  •  Why? We have mass!
  •  Anything with mass cannot go the speed of light due to special relativity!
© lbranch 2013