Unit

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Unit2 Motions of the Earth, Moon and Sun
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What do you think?

• In one well-written paragraph, explain why we see
  different phases of the moon.
• Write your name and place any diagrams on the
  back of the paper.

3
Astronomy in Ancient SocietiesWhy did people
watch the sky?

• Navigation at Night
• Time of Day
• Marking the Seasons
• Calendars
• Major part of religion

4
Observations/Observatories

• Chinese recorded observations 5000 years ago
• Mayan observatory with viewing holes

5
What can you see with the unaided eye?

• Which of the following dates would have the Sun
  above the horizon for the most hours?
• March 21
• June 22
• September 22
• December 23

6
What can you see with the unaided eye?

• Which of the following dates would have the Sun
  above the horizon for the most hours?
• March 21
• June 22
• September 22
• December 23

7

• In which direction is the Sun at noon in the
  winter?
• East
• South East
• South
• South West
• West

8

• In which direction is the Sun at noon in the
  winter?
• East
• South East
• South
• South West
• West

9

• Suppose the Sun rises due east. When will the Sun
  next rise due east?
• Tomorrow
• Six months
• A Year
• Never

10

• Suppose the Sun rises due east. When will the Sun
  next rise due east?
• Tomorrow
• Six months
• A Year
• Never

11

• If you see the Moon rise tonight at 900 p.m.,
  approximately what time will it rise tomorrow
  night?
• 800 p.m.
• 900 p.m.
• 1000 p.m.
• 1100 p.m.

12

• If you see the Moon rise tonight at 900 p.m.,
  approximately what time will it rise tomorrow
  night?
• 800 p.m.
• 900 p.m.
• 1000 p.m.
• 1100 p.m.

13

• Approximately how many hours of daylight do you
  get in the summer?
• Less than 12
• Exactly 12
• 12 to 16
• Over 16

14

• Approximately how many hours of daylight do you
  get in the summer?
• Less than 12
• Exactly 12
• 12 to 16
• Over 16

15

• How much time is there between full Moons?
• A day
• A month
• Three months
• A year

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• How much time is there between full Moons?
• A day
• A month
• Three months
• A year

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Movement of the Moon

• The moon moves east to west across the sky each
  night
• The moon rises one hour later than the precious
  night
• The moon goes through phases over a 29.5 day
  period from full moon to full moon
• The moon waxes (builds) to the right.
• A full moon rises exactly at sunset
• We always see the same face of the moon because
  it rotates on its axis at about the same speed at
  which revolves around the earth.
• The moon moves counter clockwise around the earth.

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Some useful animations

• moonphase.mov
• http//www.astro.wisc.edu/dolan/java/MoonPhase.ht
  ml

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Motion in the Solar System

• The Moon has two relevant periods
• 29.5 days between new moons (moon directly
  between us and the sun)
• Only 27.3 days until it reappears in the same
  place relative to the stars.

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Phases of the Moon
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Calendars and the Lunar Month/Year
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Lunar Eclipses
Alignment of the Sun, Moon, and Earth ?
Shadows Shadows are responsible for eclipses, NOT
PHASES OF THE MOON
MrEclipse.com
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Animations of a Lunar Eclipse

• http//csep10.phys.utk.edu/astr161/lect/time/lunar
  _anim.html
• http//www.classzone.com/books/earth_science/terc/
  content/visualizations/es2504/es2504page01.cfm?cha
  pter_novisualization

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Lunar Eclipses
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Solar Eclipse
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Solar Eclipses
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Solar Eclipses - Animations

• http//csep10.phys.utk.edu/astr161/lect/time/eclip
  se_anim.html
• http//www.ioncmaste.ca/homepage/resources/web_res
  ources/CSA_Astro9/files/multimedia/unit3/eclipse_m
  ovie/eclipseMovie.html

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Predicting Eclipses http//sunearth.gsfc.nasa.gov
/eclipse/SEcat/SEdecade2001.html