GALAXIES

1
GALAXIES

• Galaxy- cluster of stars, gas and dust held
  together by a gravitational force dark matter
• Dark matter- mysterious gravitational pull. Maybe
  at the center of galaxies? Maybe black holes. Not
  much known about it.
• We study galaxies because of the amount of light
  they produce, easier to measure at great
  distances.

2
TYPES OF GALAXIES

• Spiral- shaped like a pinwheel, dense at the
  center with arms that extend outward.
• Milky Way (our galaxy) is a spiral galaxy. The
  diameter of the MW is 100,000 light years. Yikes
  thatss far!
• Irregular- No real definite shape to these
  galaxies. Thought to be the youngest than others.
• Elliptical- shaped like a football, oblong. No
  arms. Older galaxies.

3
GALAXIES

• Cluster- group of galaxies.
• Rate of galaxies movement can help us determine
  state of the Universe.
• Doppler Effect

4
(No Transcript)
5
(No Transcript)
6
(No Transcript)
7
(No Transcript)