Transcript Chp. 3 The sun-earth

Big Idea
What natural phenomena do the
motions of Earth and the Moon
produce?
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The Sun
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Nearest star to Earth
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150 million km from Earth
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it is ENORMOUS
Diameter is 100 times greater than Earth
Can you write 2 more important points of the
Sun from the book?
1.
2.
Intro vocab books
EARTH’S ORBIT
HTTP://WWW.YOUTUBE.COM/WATCH?
V=R2LP146KA5A
EARTH’S ORBIT
THE EARTH ORBITS AROUND THE SUN.
1 WHOLE COMPLETE ORBIT IS CALLED A
REVOLUTION.
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TAKES 365.24 DAYS
SUN’S GRAVITATIONAL PULL
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The Suns gravity pulls on the
Earth
 The more mass & closer
objects are the stronger the 
gravitational pull.
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The Earth revolves around
the Sun and the gravity
keeps it revolving.
Sir Isaac Newton's law of universal
gravitation states in part that "every
object in the universe attracts every
other object." That applies to celestial
bodies in the solar system as well.
While the Sun's mass exerts a much
greater gravitational pull on Earth than
Earth does on the Sun, both bodies
attract one another. The Sun's great
mass keeps its eight planets circling it;
by comparison, Earth's gravitational
field is small.
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EARTH’S ROTATION
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rotation-
SUN’S APPARENT
MOTION
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rotation axis-
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http://www.youtube.com/watch?v=9n04SEzuvXo
2 points of Earth’s rotation:
1.
rotates COUNTERclockwise
2.
takes 24 hours to complete
rotation (day to night)
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Sun’s apparent motion
1. rises in the East and
sets in the West?
only appears to because
we rotate
counterclockwise. (it is
actually West to East)
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.The more sunlight
that reaches a part of
Earth’s surface, the
warmer that part
becomes.
Because it is curved,
different parts receive
different parts of sun.
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With a tilted surface,
light is more spread
out.
As you move away
from the equator, the
Earth becomes more
tilted.
This means near the
poles receive less sun.
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The earth is closest to
the sun in Jan.
It is the tilt of the
Earth’s rotational axis
combo with Earth’s
motion, that causes
seasons.
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North end of the
rotation axis is toward
the Sun. Northern
hemisphere receives
more sun.
Temps high
Daylight longer
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What about the
Southern
Hemisphere?
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North end of axis is
away from the Sun.
Short days
Colder temps.
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What about the
Southern Hemisphere
is towards the Sun?
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Solstice is a day
Earths rotation axis is
most toward or away
from the sun.
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equinox when Earth’s
rotation axis is
learning along Earths
orbit.
neither toward nor
away.
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http://www.youtube.
com/watch?v=WLRA
87TKXLM
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Does the Moon emit light?
No, it is a solid object that is just reflecting the Sun’s light.
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Look at Moon Chart. Page 81.
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What is the Mass of the Moon?
1.2% of the Earth’s Mass.
What is the Diameter of the Moon?
27% of the Earth’s Diameter
Both revolution and rotation of the Moon
take 27.3 days.
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The Moons Surface:
creation of craters:
objects from space crashed into the
Moon.
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What is a maria:
Large, dark flat areas on the Moon.
they are made by lava.
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Highland
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Moons revolution and rotation are
the same causing the same side to
face the Earth.
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Near side
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Far side
LUNAR CYCLE
THE MOTION OF THE MOON
AROUND THE EARTH CAUSES
PHASES.
HTTPS://WWW.YOUTUBE.CO
M/WATCH?V=BWEAQCTUP1C
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Waxing phase is when
more of the Moon’s near
side is lit.
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Waning phase is when
less of the Moon’s near
side is let.
1 lunar cycle takes
around 4 weeks / 29.5
days
WAXING PHASE: MORE
MOON IS LIT.
WANING PHASE: LESS OF THE
MOON’S NEAR SIDE IS LIT.
UMBRA:
THE CENTRAL, DARKER PART OF A SHADOW
WHERE LIGHT IS TOTALLY BLOCKED.
PENUMBRA:
THE LIGHTER PART OF A SHADOW
WHERE LIGHT IS PARTIALLY BLOCKED.
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The moon passes between Earth
and the Sun.
Only happens in a New Moon
solar eclipse- When the Moon’s
shadow appears on the Earth’s
surface.
https://www.youtube.com/wa
tch?v=6bAF8fF4pe4
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Total Solar Eclipses:
seen only in the Moon’s umbra
Moon appears to cover the Sun
completely and it takes 7 min.
http://www.theguardian.com/
science/video/2012/nov/14/so
lar-eclipse-australia-video
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Partial Solar Eclipse:
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Can be seen in the penumbra
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Why can’t solar eclipses occur
every month?
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When the moon moves
into the Earth’s shadow
is a lunar eclipse.
the Earth is in line
between the Sun and
moon.
Only occurs during a full
moon phase.
https://www.youtube.co
m/watch?v=lcRp1jKJmJU
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Total lunar eclipse:
The entire Moon moves
through Earth’s umbra, a
total lunar eclipse occurs.
Earth’s atmosphere
deflects some sunlight into
Earth’s umbra.
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Partial eclipses:
Only part of the Moon
passes through the
Earth’s umbra.
Why don’t lunar
eclipses occur every
month?
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https://www.youtube.c
om/watch?v=5ohDG7R
qQ9I
tides
Ocean water rises or
falls. It is not a wave.
The moon’s gravity is
slightly stronger on the
side of Earth facing the
Moon.
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Spring tide
During full and new
moon. Higher high
tides and lower low
tides.
Neap tides
week after spring tide
Sun-Earth-Moon form a
right angle
High tides are lower
Low tides are higher