Transcript The Outer Planets

The Outer Planets
2012
The Outer Planets
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The outer
planets are
made of gases.
The outer
planets are
very large.
Gas Giants
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Separated from the 1st
zone by the asteroid belt,
the 2nd Zone contains the
gas giants.
Made of the lightweight
elements Hydrogen,
Helium, Carbon, Oxygen,
and Nitrogen.
All are much larger than
the Earth, with 15-300
times the mass, and 4-11
times the diameter.
Not believed to have solid
surfaces.
Have rings and many
satellites.
Gas Giants Atmospheres
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Since they have so much
mass, their strong gravity can
keep even light gases from
escaping.
Atmosphere tends to resemble
the sun (75% H, 24% He, 1%
other gases).
No well defined surface.
Gases just get denser and
denser as you go deeper.
Becomes liquid metallic
hydrogen, which has
properties of liquids and
metals. Exist only under high
pressure. Causes Jupiter's
magnetic field.
Gas Giants Cores
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Gas giants are
believed to have
solid cores made
of rock,, ice,
frozen carbon
dioxide, and
other
compounds.
Cores would be
several times
the size of the
Earth.
Jupiter, King of the
Roman Gods
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Named for Jove,
the King of the
Roman Gods.
Roman name for
the Greek god
Zeus.
Often the term
Jovian is used to
describe things
pertaining to
Jupiter. Example:
the Jovian moons.
Jupiter
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Believed to be a failed
star, lacking the mass
to become a small star.
Most massive planet in
solar system.
Has over 60 satellites.
Density is 1.33g/cm3.
Rotates every 10
hours.
Takes 12 years to orbit
the sun.
Gravity almost 2.5
times that of the Earth.
Jupiter Atmosphere
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Mainly hydrogen
with some helium.
Very active weather
systems.
Forms colorful
bands and swirls.
Has hurricanes that
last for 100’s of
years.
Great Red Spot
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The red spot is a
huge storm that has
been continuously
going on Jupiter for
over 400
years. Winds inside
this storm reach
speeds of about 270
mph. With a
diameter of 15,400
miles, this storm is
almost twice the size
of the entire Earth.
Jupiter's Moons
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Galileo discovered the four
largest. Io, Ganymede,
and Callisto are larger than
our own moon.
Europa has a icy crust and
is believed to have liquid
water oceans below the
frozen surface.
Io has many active
volcanoes.
Has 63 moons, most of
any planet in our solar
system.
Ganymede is the largest
moon in our solar system.
Missions to
Jupiter
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http://www.window
s.ucar.edu/tour/link
=/jupiter/space_mis
sions.html
http://www.solarvie
ws.com/eng/craft2.
htm#jupiter
Shoemaker Levy 9
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In July 1994, Comet
Shoemaker-Levy 9 collided
with Jupiter with spectacular
results (left). The effects
were clearly visible even
with amateur telescopes.
The debris from the collision
was visible for nearly a year
afterward with HST.
Captured by Jupiter's strong
gravity, the comet was torn
into over 20 fragments that
struck Jupiter, each with a
force of millions of megatons
of energy.
This has renewed NASA’s
interest in tracking objects
that might get close to Earth
one day.
Jupiter Facts
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Diameter: 11 earth's
Distance: 5 Au
Atmosphere: mainly hydrogen with some
helium
Features: active weather with storms that
last for 100s of years (GRS)
Largest planet
Over 60 moons, most in our solar system
Life: none as we know it. Cold, no known
surface.
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Saturn the God
Saturn was the Roman God
of the Harvest and of Time.
Father of Jupiter, Neptune,
and Pluto.
The Roman name for the
Greek god Cronos.
Saturnalia was the midwinter festival in Saturn's
honor. It lasted seven
days, and there was much
merrymaking. Public
business was suspended
and schools were closed.
Parents gave presents to
their children.
Saturn Facts
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2nd largest planet in solar
system.
A “day” on Saturn is a
little over 10 hours long!
It takes 29 years to orbit
the sun.
Almost 10 times larger
than Earth.
Most visible rings of any
planet.
Density is 0.69 g/cm3.
If a large enough ocean
could be found, Saturn
would float in it!
Saturn’s
Atmosphere
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Similar to Jupiter’s,
mostly hydrogen with
some helium.
Storms not as large or
as long lived as
Jupiter's.
Clouds are thicker,
blocking views to
lower layers. Explains
the lack of banding
compared to Jupiter.
Saturn’s Moons
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Has over 40 moons, 15 or so that are large
enough to be called major moons.
Titan
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Titan has an
atmosphere made of
about 99% nitrogen
and 1% methane.
Has a pressure of 1.6
atmospheres.
Completely covered
by thick clouds that
are similar to smog
on Earth.
The second largest
moon, it is larger
than Pluto and
Mercury.
CassiniHuygens
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The Huygens probe
actually parachuted
into the atmosphere of
Titan on 14 January
2005.
It took pictures and
collected data all the
way to the surface. It
survived the landing
and sent back pictures
of the surface it landed
on.
Saturn’s
Rings
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Very spectacular. Not
at all solid.
Made of tiny bits of
ice, dust, and rock. A
few are up to a
kilometer across.
Only about a kilometer
thick.
The Cassini space
probe actually passed
through the outer ring
as it slowed down to
enter orbit.
Saturn Facts
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Diameter: 9 times larger than Earth
Distance: 10 Au
Atmosphere: 96% Hydrogen 4% Helium
Features: Has short storms, brilliant rings
orbit it that are made up of bits of ice,
dust, and rock
2nd largest planet
Life: no life likely, although Titan and
Enceladus have possibilities.
Uranus the God
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URANUS: Great
primeval God of the
Sky. Born of GAIA,
the Earth, he
covered the world
in the form of a
vast bronze dome
and ruled over
everything.
Uranus Facts
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Diameter is like 4
Earth’s.
Mass is 14.5
Earth’s.
Takes 84 years to
revolve around the
sun.
Day is a little over
17 hours long.
Has more than 20
moons.
Uranus Axis
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Uranus is considered
unusual because the
planet is tipped on its
side. The poles actually
point towards the Sun.
its magnetic field is
tilted 60 degrees from
the axis of rotation.
It is believed that
Uranus was struck by a
large object that
knocked Uranus on its
side.
Uranus Seasons
Uranus Atmosphere
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First, there is
absolutely no detail
in the cloud cover.
Only when pushed
to the maximum
level of color
enhancement and
contrast on
computers do
scientists start to
see small swirls in
the atmosphere.
Uranus Moons
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5 large and many small
moons.
Titania is the biggest
moon of Uranus. It is
about half the size of
our moon. Titania is
covered by many small
craters, a few huge
impact basins ice cliffs,
and fault lines.
Ariel: The brightest
moon of Uranus.
Youngest surface of
Uranus' moons, the
least cratered. Has long
valleys and canyons.
Uranus
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Diameter:4 Earth’s
Distance:19 AU
Atmosphere:82% Hydrogen 15% Helium
Features: extreme seasons because axis is
tipped on its side and no detail in cloud
cover
Life: no life, too cold, atmosphere and
surface would not allow life as we know it.
Neptune the God
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Neptune is the
Roman god of the
sea.
The Romans
modeled him after
the Greek god
Poseidon.
Neptune
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Neptune revolves on its
axis every 18 hours.
It takes 165 years to
revolve around the sun
once.
Has the mass of 17
Earths.
Has 13 moons.
Diameter is almost 4
times larger than Earths.
Blue-green color is from
the methane in the
atmosphere.
At times it is the furthest
planet from the sun.
Neptune Atmosphere
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80% hydrogen,
19% helium, and
1.5% methane.
Has icy clouds and
enormous storms.
Has the fastest
winds in our solar
system.
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Triton
Neptune's largest moon is
named Triton. Triton is much
larger than any of the planet's
other moons.
Triton is a very cold place, so
the moon is covered with ice.
Even though Triton is cold
there is a lot going on there. It
has geysers like the ones at
Yellowstone Park on Earth.
The geysers shoot ice 8 km (5
miles) high into Triton's thin
atmosphere! There may be
water under the ice at Triton.
It is even possible that there
might be life in that water. The
interior of Triton is probably
geologically active.
Neptune’s Rings
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Neptune's rings are
much darker than
Saturn's bright
rings.
Saturn's rings are
made of ice, which
reflects lots of light.
Neptune's rings are
probably made of
rocks and dust.
Rocks and dust
don't reflect as
much light.
Neptune Facts
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Diameter: 4 times the size of Earth
Distance: 30 Au
Atmosphere: 80% Hydrogen 19% Helium
1.5% Methane
Features: At times it is the furthest planet
from the sun. Icy clouds and enormous
storms, one called the Great Dark Spot.
Life: possible life on one of its moons
called Triton
Pluto the God
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Pluto was the Roman name
for Hades, the Greek god of
the Underworld.
Discovered in 1930 by Clyde
Tombaugh using a blink
comparator. This allowed
astronomers to quickly look
for differences in two
photographs shot on
different nights of the same
part of the sky.
Pluto
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Once thought of as usually the
furthest planet from the sun.
2/3rds the size of our moon.
Has one large moon, Charon,
and two smaller ones, Nix and
Hydra.
So cold that oxygen and
nitrogen in its atmosphere is
frozen solid except when Pluto
is nearer the Sun.
Only planet not visited by a
spacecraft.
Pluto takes 248 years to make
one orbit around the sun!
Pluto’s Atmosphere
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When Pluto comes close enough
to the sun, the surface of solid
Nitrogen sublimates to produce
a substantial atmosphere with
winds and clouds.
Because the planet is so small,
however, it does not have
enough gravity to bind an
atmosphere for very long. Thus
Pluto's atmosphere is being
rapidly produced and rapidly
lost at the same time.
This means that the atmosphere
is not in equilibrium.
Similar to comets when they get
close to the Sun.
Pluto’s Orbit
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Pluto has the most eccentric orbit of
all the planets in the solar system.
Its orbit takes it to 49.5 AU at its
farthest point from the Sun. And its
orbit takes it as close as 29 AU to
the Sun.
That means that Pluto's orbit draws
within the orbit of Neptune, as can
be seen in this drawing, making
Pluto the 8th planet rather than the
9th planet for roughly 20 years at a
time.
Pluto was the 8th planet from
January 1979 to February 1999.
Neptune is now the 8th planet for
over 200 years!