Transcript properties of light, comets, meteoroid impact and aurora borealis

Anatomy of a Comet
http://airandspace.si.edu/exhibitions/exploring-theplanets/online/comets/comet_anatomy.html
Comet Photo
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http://photojournal.jpl.nasa.gov/figures/PIA1122
8_fig1.jpg
Meteoroid Impact Connections p
128
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Manicouagan Cretor – Can be seen from space
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Charlevoix
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Hudson Bay
Aurora borealis (Northern Lights)
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Occurs at the North and South Poles.
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They look like ribbons of light in the sky.
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Occurs in the thermosphere in the sublayer
ionosphere.
It DOES NOT occur in the exosphere because
the particles are too far apart.
They are called Aurora australis at the South
Pole.
Aurora borealis – from space
Northern Lights – from earth
Aurora Borealis Videos
http://www.youtube.com/watch?v=1MI3YDGgtN4
https://www.youtube.com/watch?v=_r1aDnfzWu4
http://www.youtube.com/watch?v=Ju7bpeOPGZo
Phases of the Moon
Why does the moon have different
phases?
• One half of the moon is always illuminated (lit by
the sun) and the other half of the moon is
always in darkness.
• The moon orbits counterclockwise around the
earth.
• The part of the moon that we see (the
illuminated side, the dark side or the proportion
of both) depends on the moon’s orientation
within its orbit, in relation to the earth and the
sun.
Waxing – The moon is approaching a full moon
and the illuminated side of the moon is getting
bigger.
Waning – The moon is approaching a new moon
and the illuminated side of the moon is getting
smaller.
Phases of the Moon
http://www.youtube.com/watch?v=FI2tP8dpwNA
https://www.youtube.com/watch?v=wz01pTvuMa0
http://www.youtube.com/watch?v=2aFGNGEcDOk
http://www.youtube.com/watch?v=FhokvJZFURg
Universal Gravitation
• Gravitation is a force of mutual attraction
between bodies (objects).
• The earth pulls you to the ground with a strong
attractive force (gravity) but, with a weaker
attractive force, you also pull the earth to you.
• The earth pulls the moon towards itself and the
moon pulls the earth towards itself. The force
with which the earth pulls the moon is stronger
so the moon orbits around the earth.
• The sun pulls the earth towards itself and the
earth pulls the sun towards itself. The sun’s
gravitational pull is stronger so the earth orbits
around the sun
Solar System – Sizes, Distances,
Composition p 357
http://ronyerby.com/ss/Outer.html
http://ronyerby.com/ss/Inner.html
Characteristics of Light
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Light is a form of radiant energy.
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Light travels in a straight line.
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Light bounces off surfaces.
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Diffuse reflection – when light bounces of
irregular surfaces. We see the object.
Specular reflection – when light bounces off
smooth surfaces. We see an image (ex: mirror,
or a still lake.
Assignment
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Explain each of the following phenomena using
the properties of light:
Cycles of day and night, seasons, phases of the
moon, eclipses
Solar System Project
• You will make a 3 D Model of the solar system.
• You will include all of the planets, the sun and
the moon.
• The planets will be color coded according to
their substance composition.
• You will make the planets TO SCALE according
to their diameter.
• You will make the distances TO SCALE as well.
• You may have to use two different scales.
• You may use any materials you want.