Transcript The Jovian Planets

The Jovian Planets
Chapter 9
The order of things
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___________ – The largest planet
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The planet formerly known as Pluto (just
kidding, I just wanted to make fun of
Prince) Not a planet anymore
Jupiter
Gas giant
 Temperatures are extremely cold 150 K
(100 below freezing Fahrenheit)
 Composed of mostly liquids and gases.
 The Roman king of the gods. The Romans
did not know how large Jupiter was when
they first named it.
 Jupiter is 10 times the size of Earth and
300 times in mass
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The appearance of Jupiter
A Result of banding of clouds in the
atmosphere.
 Jupiter’s atmosphere is mostly Hydrogen,
Helium, and methane.
 The clouds that form the belts commonly
seen on Jupiter consist of water, ice and
ammonia compounds.
 Jupiter Rotates MUCH faster than Earth
 So much so that it bulges at the equator
and is not a perfect sphere.
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Jupiter’s Surface
Jupiter’s surface is masked by clouds
 Astronomers are limited to theories to
explain the surface and interior of the
planet.
 The extreme cold and the huge densities
have a tremendous impact on the make
up of the planet.
 The average density is approximately 1.3
g/cc. This indicates that the Jupiter is
mostly hydrogen.
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Jupiter’s Surface
Calculations based on size, mass, and density
indicate what is below the clouds of Jupiter.
 Jupiter’s huge mass means a huge
gravitational force.
 The gravitational force of Jupiter is so great it
causes gases to form liquids
 Compounds in the liquid state are compressed
even further into a metallic liquid
 Remember the Main component of Jupiter is H
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Most astronomers theorize that Jupiter
and the Sun have similar components.
 Relative abundance
 If that is the case that means Jupiter also
has some heavy metals.
 Where would the heavy metals be found?
 Because of their densities have settle deep
into the core.
 See figure 9.2 for an illustration of the
interior of Jupiter.
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Jupiter’s Interior affects its Atmosphere
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Jupiter’s atmosphere has convection currents. This
convection results in severe winds.
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____________ current – The rising and sinking motions in
a liquid or gas that carry heat upward through the material.
Jupiter’s interior generates more heat energy than it
receives from the Sun
Astronomers believe that Jupiter’s tremendous
gravitational pull is causing elements such as He to
collapse into the core. The movement of the
elements is believed to be the source of the heat.
As planets form they shrink as there gravity
increases. Some scientists believe that Jupiter may
still be shrinking.
Jupiter’s Whirling Gases
Warm gases rise in the atmosphere and
dissipate heat into space.
 The cool gas then sinks back to the
surface.
 Stationary objects have convection
currents that cycle from the interior to the
exterior. Basically gasses rise and then fall
toward the equator or poles.
 HOWEVER, Jupiter is rotating. The
rotation of Jupiter causes the convection
currents to move in an eastward direction.
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The Coriolis Effect
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On Jupiter the ________ effect generates
large wind systems – Jet Streams, and
cloud belts.
 On Earth the Coriolis effect makes storms
spin
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Jupiter’s Magnetic field
Just like Earth, Jupiter generates a magnetic
field.
 The magnetic field is produced by the
rotation of the planet and convection in a
metallic core.
 Because Jupiter is so large and spins so fast,
its magnetic field is vary strong. It is over
20,000 times stronger than Earth’s!
 The coriolis effect and magnetic field cause
Northern and Southern Lights on Earth as
well as Jupiter.
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The Ring of Jupiter
Saturn and Uranus both have rings
 Scientists decided to look for rings around
Jupiter.
 As it turns out, Jupiter also has a ring.
 It is VERY small, and difficult to see
because of solar radiation.
 The Probe Voyager I was able to take
pictures of the ring
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The Ring
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Jupiter’s ring is composed of small rock and
dust particles trapped by Jupiter’s gravity.
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The particles are so small that collisions gases
are able to push them around!
They are slowly drifting closer to Jupiter’s
atmosphere. And being incorporated into
the planet.
 The Rings are being “replenished” by the
collision of tiny satellites of Jupiter that
occasionally collide and fragment.
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The Moons of Jupiter
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The first to see the Moons of Jupiter was
__________.
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The Galilean moons are larger
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He only saw 4 of the 63 moons, 48 of them are
named
Most of the other moons are too small to see
from Earth and were only photographed by the
Voyager Spacecraft.
The Galilean moons are: _____, ________,
_________, and ___________
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All are larger than our moon except for Europa.
Ganymede is even larger than Mercury!
Moon formation
Some astronomers believe the moons of
Jupiter formed in a similar manner to the
formation of the solar system.
 Jupiter’s large mass caused enough
gravitational pull to have trap some
planetesimals that kept colliding together
and formed the moons. (Similar to planet
formation.)
 Evidence also suggests that Jupiter released
enough heat to affect moon formation by
altering moon density and even the
compositions of the moons.
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Io
_________ to Jupiter.
 Tidal forces move the crust which results
in __________ activity.
 The unique color of Io is a result of the
lava flows and Sulfur outpourings.
 Shows ________ craters because of the
constantly changing surface due to the
severe volcanic activity.
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Europa
The _________ Galilean moon.
 Appears white because of the frozen ____
on the crust.
 The red streaks are mineral rich liquid
water that seep from underneath.
 Europa shows _____ evidence of craters!
 Any asteroids that strike the moon leave
no marks because of the liquid water
underneath a glacier like sheet of ice.
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Callisto and Ganymede
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Callisto
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Similar in appearance to our moon, but that is
about the extant of any similarities.
Evidence suggest it too has an icy crust and a
liquid water ocean underneath.
However, there is evidence of craters
Ganymede
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Cratered, but not as many as Callisto
Shows some evidence of tectonic activity
Saturn
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The second largest planet
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10x larger than Earth, 95 x its mass
 Very low density – suggesting Saturn is
made mostly of ___________
 Believed to be similar to Jupiter in structure
 Even though Saturn is similar to Jupiter, it is
cooler and farther from the Sun
 Results in less noticeable banding of clouds.
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The most striking features of Saturn:
The rings
 First seen by __________
 The rings are very wide (over 100,000km)
 BUT they are also Very thin. (few hundred
meters thick)
 The rings are made of very small particles
ranging in size from a few cm to meters
 Composed mainly of frozen water!
 Darkly colored rings contain larger
amounts of Carbon
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Origin of Rings
Rings were believed to be formed from
material produced as a result of moons
breaking apart.
 Moons can be ripped apart because of tidal
forces
 Occurs when a moon gets too close to a
larger planet.
 The Roche limit –
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The Roche Limit
First predicted and mathematically proven
by M.E. Roche
 Occurs because the force of the planet
pulls more on the side of the moon closest
to the planet.
 When the density of the planet and the
moon are equal, the Roche limit is 2.44
planetary radii.
 See figure 9.14
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The Roche limit applies only to objects
held together by gravity.
 Smaller objects whose shape is a result of
bonding or mechanically fastened are not
affected by the Roche limit. (it is a result
of gravity)
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The moons of Saturn
Of all the planets in the solar system, Saturn
has the most moons.
 The moons of Saturn are less dense than the
Galilean moons.
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This suggests they are made of mostly ice
The moons of Saturn are not tectonically
active.
 Titan, the largest, has an atmosphere of N
and may have “rain showers” of ethane
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Do we use ethane?
Can you imagine a scenario where we harvest the
natural resources of other planets?
Uranus
Believed to be composed of water, ammonia,
and methane.
 The core may be composed of Iron, rock and
maybe even ice!
 The methane in the atmosphere absorbs red
light and reflects blue, giving Uranus its blue
appearance.
 Uranus’ ring system is very narrow and dark.
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Probably composed of Carbon compounds
The moons of Uranus
Uranus has _____ small moons and 5
larger moons
 The smallest of the large moons, Miranda,
may have been shattered by a large
object and then re-coalesced after impact.
 It has the most extreme topography with
cliffs 2x as high as Mount Everest.
 Uranus was also hit by a large object that
knocked it on its back. The Poles actually
point toward the sun!
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Neptune
Outer most plant in the solar system.
 30 AU from the Sun
 Has a similar composition as Uranus.
 Contains an atmosphere of methane and a
“dark spot” similar to Jupiter’s red spot.
 Neptune generates convection currents
which result in a coriolis effect.
 Winds reach 1300 miles per hour
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Neptune
Also has a ring system. They are very
narrow and composed of more dust than
other ring systems.
 Astronomers believe they will collapse into
Neptune in a million years or so.
 Neptune has two sets of moons. Six small
moons orbiting close to the planet and
then two other moons orbiting at a great
distance from the planet.
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Kuiper Belt Objects (KBO)
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The Kuiper belt is an area in the solar
system extending from the orbit of
Neptune to 50 AU from the sun.
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Pluto and its moon Charon are considered
to be Kuiper belt objects
 Another Kuiper belt object recently
discovered is Eris. It is actually larger
than Pluto
 Neptune’s moon Triton is a captured KBO
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