History of Astronomy

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History of Astronomy

• Views of the Solar System

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How did all of SPACE start?

• No one knows for sure, but its believed that
• Between 10 to 20 billion years ago the entire
  universe was smashed into a TINY atomic dot. It
  was so hot that it exploded causing the Big Bang,
  the birth of the universe.

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What did it look like?

• At first, the universe was a very hot, fireball
  of expanding, cooling gas.
• After about one million years the gas started to
  condense to form the objects in the sky.

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How did different views of solar system and
theories about what was going on in outer space
develop and change over the years?Lets start
with Aristotle
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Aristotle (Air-u-stot-ul)
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Aristotle

• The Grandfather of Science
• Believed in the Geocentric Model
• Thought the planets and stars moved around Earth
  in perfect circles

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Geocentric Model

• Geo means Earth
• centric means center
• -----------------------------------
• Earth-centered model
• Geocentric means everything revolves around
  EARTHweird!

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What technology did Aristotle use?

• Naked eye
• Observed Earth is a sphere
• No telescopes!

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Where was Aristotle from?When did he make his
observations?

• Scientist from Greece
• 350 B.C.

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Ptolemy (toll-u-me)
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Ptolemy

• He believed in the GEOCENTRIC MODEL
  (Earth-centered)
• Predicted the positions the planets are in now

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What technology did Ptolemy use?

• Naked eye
• No telescopes!

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Where was Ptolemy from?When did Ptolemy make
his observations?

• Greek
• astronomer
• 140 A.D.

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Geocentric Model
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Copernicus (cu-per-ni-cus)
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Copernicus

• Founder of Modern Astronomy
• Believed in Earths rotation on its axis once
  each day
• AND
• that Earth revolves around the Sun once a year.
  This is known as the HELIOCENTRIC MODEL.

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Heliocentric Model

• HELIO means Sun CENTRIC means center
  Sun-centered model
• This was radical, new thinking and not easily
  accepted by other scientists

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What technology did Copernicus use?Naked eye
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Where was Copernicus from?When did Copernicus
make his observations?

• From Poland
• Lived more than 100 years later, in the
  1500s1543 A.D.

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Galileo
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Galileo

• Discovered Jupiters 4 largest moons
• Used the telescope to prove Copernicus was
  correctthe Sun is the center of our Solar System
  (Heliocentric)

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Galileo also

• Observed that we can see phases like our moon
  when we look at Venus!

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What technology did Galileo use?

• TELESCOPE!
• Made a telescope that could enlarge objects up to
  20 times! WOWthats not much It is less than
  most binoculars today!

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Where was Galileo from?When did he make his
observations?

• Scientist from Italy
• Lived 100 years after Copernicus 1610 A.D.

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Heliocentric Model
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Tycho Brahe (Teek-O)
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Tycho Brahe

• Made careful observations
• Recorded positions of the planets
• Believed in Heliocentric Model

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What technology did Tycho use?

• Naked eye
• Tychos Observatory
• ?

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Where was Tycho from?When did he make his
observations?

• From Denmark
• Late 1500s

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Kepler
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Kepler

• Used Tychos data to find elliptical orbits of
  the planets (not perfect circles!)
• Heliocentric Model

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What technology did Kepler use?

• Naked eye
• Math calculations
• Telescope

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Where was Kepler from?When did he make his
observations?

• From Germany
• Worked in the 1500-1600s