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Saturn
Presentation by: Heather DeRoy
Basic Facts
6th Planet from the Sun
 2nd Largest Planet in the Solar System
 7 thin, flat rings
 62 Moons
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Ancient Observations
Farthest planet prehistoric astronomers knew
 Used in mythology
 Planet can be seen by Earth with the naked
eye, but the rings cannot
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Saturn the Name
Roman god of agriculture and
harvest
 Father of Ceres, Jupiter, Pluto,
and Neptune
 Ruled during the Golden Age of
Men
 Saturn represents limits of
control as it was thought to be
the limit of the Solar System
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Unlucky Saturn
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In Astrology, Saturn is blamed for all
things sad, unfortunate, and terrible
Size of Saturn
2nd largest planet in the
Solar System
 95 Earth masses
 “Gas Giant” along with
Jupiter, Uranus and
Neptune
 Diameter 120,540km
(10x Earth)
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Density
Lowest of all the planets
 1/10 the density of Earth
 2/3 dense as water
 Saturn would float in water!
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Saturn’s Orbit
Aphelion ~ 10.1 AU ; Perihelion ~ 9.0 AU
 Period of Orbit – 29.46 Earth years
 Axis tilt of 27 degrees
 Eccentricity of .056
 Rotation is 2nd fastest of known planets
 Saturn rotates ~ 10 hours 39 minutes
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Shape of Saturn
Rapid rotation causes the planet to bulge
 Oblate spheroid – flattened at poles and
bulges at equator
 Rings
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Saturn’s Rings
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Discovered by Galileo (1600s)
Rings tilt at same angle as
equator
~20m thick
93% water ice composition,
7% amorphous carbon
7 rings made up of thousands
of ringlets, made up of billions
of ice particles
Particles range in size from
dust to a car
2 Main Ring Theories

Theory 1
 Remnants

of destroyed moon of Saturn
Theory 2
 Rings
left over from original nebular material that
formed Saturn
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Some ice comes from the moon
Enceladus’ ice volcanoes
Saturn’s Surface
Saturn is a giant ball of gas
 Believed to have no solid surface
 Inner core of iron and rocky material
 Outer core of ammonia, methane, and
water
 Liquid metallic hydrogen surrounds outer
core
 Hydrogen and helium in a viscous form
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Saturn’s Atmosphere
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The surface and
atmosphere merge
(hydrogen and helium)
Dense clouds cover
Saturn
Difference in temperature
and altitude cause
patterns and color
differences in cloud tops
Hexagon clouds at North
Pole
Temperature
Tilt of axis causes
seasons on Saturn
 Each season = 7.5 Earth
years (Saturn takes 29x
longer than Earth to
revolve)
 Top of clouds is -175
degrees C (-285 F)
 Below clouds is hot –
planet gives off 2.5x the
heat it receives from the
Sun
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Moons
62 Moons
 Largest, Titan (diameter 5,150km) is larger
than Mercury and Pluto and contains an
atmosphere
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Discovery
Galileo discovered rings 1610, though
believed they were moons on either side
 Christian Huygens first coined “Rings”
1665
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Exploration

1973, Pioneer-Saturn launched by
U.S.
 Flew
within 20,900km of Saturn
 Sent close-up pictures
 Discovery of 2 outer rings
 Found a magnetic field 1000 times
stronger than the Earth’s
Pioneer 11 Photos (1970s)
Exploration
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1977, Voyager 1 and Voyager 2
existence of 7th ring
 Discovered planet’s rings are made of ringlets
 Discovery of 9 satellites
 Atmosphere of Titan is nitrogen
 Confirmed
Photos from Voyager 1
Saturn
 Haze over Titan
 F Ring
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Photos from Voyager 2
Saturn
 Iapetus
 Enceladus
 Titan
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Exploration

1997 Cassini probe
 Began
orbiting Saturn in 2004
 Studying Saturn, its rings, and its satellites
 First spacecraft to orbit Saturn (between F and G
rings)
Cassini Probe
New Moons Daphnis and Phoebe
 Titan
 Eclipse
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Saturn Mysteries?
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Much to learn about the rings
Strange features
 Clean ice suggests only few hundred million
years old?
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Hexagon clouds at North Pole
 Rotation impossible to pinpoint
(approximate day calculated)
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References
Spinrad, Hyron. "Saturn." World Book
Online Reference Center. 2004. World
Book, Inc.
http://www.worldbookonline.com/wb/Article
?id=ar492440.
 http://en.wikipedia.org/wiki/Saturn#Planeta
ry_rings
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