Transcript Earth Science

The Sun
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99.8% of the mass of
the solar system is in
the Sun.
It controls the motion
of all objects in the
solar system.
Mercury
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Mostly solid and covered
with craters.
Its small size (smallest
planet) and high density
suggest a large iron and
nickel core.
Its atmosphere is constantly
being replenished and
destroyed by solar wind.
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This causes extreme
temperature fluctuations
(-173o C to 427o C)
Venus
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Venus is similar in size and
composition to Earth
(slightly smaller).
Thick clouds of CO2 and
sulfuric acid cover the
planet causing an intense
greenhouse effect (464o C).
Retrograde motion – Venus
rotates clockwise very
slowly (day is longer than
year).
Earth
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Earth is the largest rocky planet and the most dense.
Unique properties that allow for life:
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Presence of liquid water because:
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Protection from radiation:
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Distance from the Sun
Nearly circular orbit
Mild greenhouse effect
Atmosphere absorbs/reflects radiation
Magnetic field
One moon.
Mars
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Mars is the 2nd smallest
planet.
Because if it’s small size
and density, Mars has a
thin atmosphere that
contains mostly carbon
dioxide.
Water may have once
existed when Mars had a
thicker atmosphere.
Mars has two small
moons.
Moons of Mars
Phobos
Deimos
Jupiter
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The largest planet (1/10th
diameter of the Sun)
Composed mostly of
hydrogen and helium (liquid
core, gaseous atmosphere).
Has over 60 moons
including four large moons.
The Great Red Spot, a huge
atmospheric storm that has
lasted for at least 300 years.
Europa
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It is slightly smaller than
the Earth’s moon.
There may be liquid water
under the ice due to
gravitational heating.
Europa is one of the five
known moons in the solar
system to have an
atmosphere.
Saturn
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2nd largest planet.
Saturn is less dense than water (H & He). If you
could fit Saturn in a lake, it would float!
Rings are leftover debris from asteroid collisions.
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250,000 km or more in diameter, but less than 200
meters thick.
Saturn’s Moon - Titan
Larger than Mercury.
 Dense atmosphere
with nitrogen and
methane.
 Cassini probe
detected ice and
water vapor.
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Uranus
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3rd largest planet.
Also mostly H & He but
appears blue-green
because of the methane
in its atmosphere.
Faint rings detected only
because they block
starlight.
Knocked sideways by a
large passing object.
Neptune
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4th largest planet and
furthest from the sun.
Existence predicted before
it was discovered.
Like Uranus, the methane
gives Neptune its color.
Pluto
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Not a planet.
Why?
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Smaller than our moon.
Comet like composition rock and ice.
Irregular orbit.
One of many similar objects
in the outer reaches of the
solar system - dwarf planets.