History of Astronomy Lesson 2 The Moon Observed

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History of AstronomyLesson 2The Moon Observed

• Major David Rogers
• USAF (Ret)

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THE AIR FORCE COMMUNITYVALUES

• Integrity do the right thing even when nobody is
  watching
• Excellence in All We Do care enough to improve
  CONSTANTLY
• Service Before Self Military people put their
  own desires behind the needs of the country

GOOD CITIZENS DONT JUST HAPPEN!
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NC-O31 Community Values

• Integrity
• Excellence in All We Do
• Others as Myselfvalue other people as much as
  themselvespeople are of value
• Educationthey learn from everywhere
• Commitmentyou cant be a part time citizen! You
  must DO WHAT YOU SAY YOU WILL DO!

GOOD CITIZENS DONT JUST HAPPEN!
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Introduction

• If you go outside on any clear night you can
  observe one of the most obvious events
  prehistoric people would have seenthe Moons
  changing appearance.
• We can explain this event today by looking at
  the relative positions of the Sun, Earth, and
  Moon.

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Explaining the Moons Phases

• Prehistoric people would have seen the Moons
  appearance change over about one month.
• The word month comes from the word moon,
  showing that it grew from observations of the
  Moons changes.

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The Moons Phases?

• You see the same thing prehistoric man saw
• Moon rises in the east and sets in the west.
• Moon rises and sets at different times throughout
  the month, rising roughly 50 minutes later each
  day.
• Moons appearance is cyclical. It goes from
  fully lit to unobservable and back to fully lit
  in about 30 days.

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How can we explainthe Moons phases?

• We now know that the relative positions of the
  Sun, Earth, and Moon cause the Moons changing
  appearance (its changing phase).

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The Moons phases? (contd)

• The cycle of the Moons phases from new to full
  and back again. (B) The Moon's phases occur
  because we see different amounts of its lit
  surface. The pictures in the dark squares show
  how the Moon looks to us on Earth.
• Note Waxing is the quarter moon after a New
  Moon but BEFORE A FULL MOON
• Note Waning is the quarter moon following a
  Full Moon

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How can we explainthe Moons phases? (contd)

• The Sun always lights half the Moons surface,
  but we usually can see only parts of the lit
  surface from Earth because of the Moons changing
  position around the Earth.

• Notice that you can see a full Moon (position 5)
  only when the Earth is dark (between sunset and
  sunrise). Also, you can never see a new Moon.

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Lesson review (contd)

• The Sun always lights half the Moons surface,
  but we usually can see only parts of the lit
  surface from Earth because of the Moons changing
  position around the Earth.
• Only at the ________ Moon can we see all of this
  lit surface.
• Full
• A _______ moon is where the moon is not visible
  from earth.
• New

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ActivityTest yourself
In the small circles draw what the Moon looks
like from Earth at each of the Moons eight
phases.