Galaxies and formation of the universe

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Galaxies and formation of the universe
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Basic Astronomy Vocab

• Universe space and EVERYTHING in it.
• Galaxy large groups of stars (and the planets
  that surround the stars)
• Solar System a star (or star system) and the
  planets that surround it.
• Ex. Our sun and the nine planets
• There are billions of stars in our galaxy, and
  there are millions of galaxies in the universe.

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Galaxies

• There are three types of Galaxies
• Spiral galaxies- bulge at center
• and spiral arms (Milky Way)
• 2. Elliptical galaxies- massive
• blobs of stars (sphere shaped)
• 3. Irregular galaxies- no specific
• shape

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Whats in a galaxy?

• Gas clouds (NEBULAS!) the beginnings of new
  stars
• Star Clusters (groups of older stars)
• Globular cluster group of stars that looks like
  a ball
• Open cluster star groups that are located along
  the spiral disc of a galaxy

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The Milky Way Galaxy
SUN

• Our galaxy is the Milky Way
• It is a spiral galaxy
• Contains billions of stars

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• It would take two million years traveling at
  the speed of light (186,282.397 miles per second)
  to reach the Andromeda Galaxy closest galaxy to
  the Milky Way.

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Formation of the UniverseThe Big Bang Theory

• The universe was shrinking. Eventually, all the
  galaxies collided and created a HUGE explosion
  (the big bang). This caused the universe to
  expand. The expansion has lasted 10-15 billion
  years.

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What will happen in the future?

• We dont know!! Here are the possibilities
• most likely to happenThe universe will keep
  expanding and the stars will eventually run out
  of fuel (hydrogen) and go dark.
• least likely to happenGravity will pull the
  galaxies back together and all matter will be
  crushed into a black hole.