Download Jupiter=Zeus=Indra

Jupiter=Zeus=Indra
•  King of the Gods. God of sky &thunder
•  Orbital period = 11.9 years (one year in
each zodiacal constellation) @5.2 AU
Saturn = Cronus
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God of Harvest, Agriculture. Saturnday
Father of Jupiter, Neptune, Pluto.
Son of Uranus and Gaia.
Faintest + Farthest planet easily visible to naked eye
Jupiter and Saturn Physical properties
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Radius 10 Earths and 9 Earths: Volume ~ 1000 Earths
But Mass only 318 Earths and 59 Earths
so Density 1.3gm/cm3 and 0.7 gm/cm3
Not like Earth, all rock & iron =5gm/cm3
Differential Rotation
•  Jupiter: Cloud period = 9h50min @ Equator &
9h55min @ pole =Differential Rotation
•  Radio/magnetic field = 9h55min
•  Saturn: Rotation 10h14m to 10h46m
=Differential Rotation
Oblate
•  So fast that Equatorial Bulge & Flat Poles = Oblate
•  The mountain most distant from the center of Earth
is Chimoborazo
Jupiter’s
Atmosphere
•  86% Hydrogen and
14% Helium like the
sun & stars
•  Small amounts of
methane CH4,
ammoniaNH3 and
water vapor H2O
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Structure of Atmosphere
Galileo probe measured temperature, pressure etc.
Clouds in three layers – NH3, ammonia hydrosulfide &H2O
Colors from phosphorus & sulfur?
No carbon chains
Saturn’s Atmosphere
•  Composed of Hydrogen 92% &
Helium 7.4% - missing Helium!
•  Temperature of 100 Kelvin
•  Thick methane haze covers/mutes
clouds: ammonia, ammonium
hydrosulfide, water clouds
Atmospheric Bands
•  Convection = High/Low pressure
regions smeared by rapid rotation
into dark Belts & white Zones
Jupiter’s
Zonal Flow
•  Winds 550 km/hr similar
to Earth’s jet streams
Spots/Storms on Saturn
•  IR image: Dragon Storm“ produced
lightning & radio static
•  Super storm wrapped around Saturn
by a zonal flow faster than Jupiter’s
Great Red Spot
•  First observed by Hooke 1680
•  Twice the size of the Earth
•  Rising Gas produces 30km
high thunderhead-lightning
White Ovals
•  3 white ovals merged to
form Red Spot Junior
Polar Vortex
•  Spring in North allows Cassini probe to see
North pole surrounded by hexagon
•  Centered on Pole is hurricane (Vortex) with
low clouds in red & high clouds in green
(infrared)
Jupiter’s Internal Structure
•  Radiates 1.7X more energy
than it receives from the sun
•  Core temp~40,000K, not rocks
•  No solid surface
•  Liquid metallic hydrogen
Internal Energy Source
•  Radiates 2 times energy it receives from sun
•  Infrared picture shows hot spot at south pole
•  Helium precipitation: Helium & Neon
“Rain” falling on core releases heat
Jovian Planets Have Magnetic Fields
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No solid surface – critical point of hydrogen
Forms liquid metallic hydrogen @depth of 20,000km
Conducting, convecting core & rotation produces magnetic fields
Some reversed, tilted, offset?? – large magnetospheres
Jupiter’s Magnetosphere
•  Larger than sun
•  20,000 times Earth’s field
•  Jupiter’s rotation moves
field past Io-radio emission
•  Sweeping up ions, forming
Plasma torus
•  Radiation Belts & Aurora
Aurora on Saturn
•  Magnetic field aligned with rotational axis
•  Smaller mass means smaller amount of liquid metallic
hydrogen so a smaller magnetic field
•  Saturn’s radio noise in AM band – reflected by ionosphere
Jupiter is oblate because:
a)  It has differential rotation
b)  It has belts and zones
c)  It contains liquid metallic hydrogen
d)  It is emitting more heat/energy than it
receives from the sun
e)  It rotates so quickly
Jupiter’s Moons
•  Jupiter has 68 moons (2014) Many irregular satellites are captured
asteroids – orbits: retrograde, eccentric, inclined
•  Saturn 62; Uranus 27 , Neptune 14, Pluto 5; Eris 1; Asteroid Balam 2
•  ~20 discovered by DAO astronomer JJ Kavelaars; teaches Astr255
Inner Moons & Rings
•  Metis, Adrastea, Amalthea, Thebe
•  Amalthea is ~ 250km diameter
•  Inner 4 prograde moons supply material for Jupiter’s rings
Galilean Moons
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Companions/lovers of Zeus/Jupiter
Io, Europa, Ganymede, Callisto
Sizes~Moon-Mercury: Density~2gm/cc
So made of rock and ice not much iron
Tidal Heating
•  Orbital Resonance 4:2:1
Makes orbits eccentric
•  Constant rotation: “nearly”
synchronously
•  Tidal bulge of ~100meters
changes height
•  Bulge moves across moon
flexing/heating it
Callisto
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Radius =Mercury but Mass of Moon
Density 1.8 gm/cm3 so rock and ice
Orbital period= synchronous rotation= 16.7days
Heavily cratered icy surface = Old terrain
Undifferentiated but possibly water/slushy mantle
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Ganymede
Largest moon in solar system Radius>Mercury
Density ~Callisto so rock & ice
Crater counts indicate - Old dark terrain
Young bright impact craters & grooved terrain
Interaction of Ganymede’s with Jupiter’s magnetic field
indicates liquid water 170km down and 5 km thick
•  Period 4 times Io’s and 2 times Europa’s = orbital resonance
Europa
•  White smooth surface with very few
craters = very young ~million years
•  Theory: A km of ice &100km salt
water ocean
•  Salt water ocean affects Jupiter’s
magnetic field
Surface Features on Europa
•  Observe: Cracks & compression
ridges & crust broken & moved
•  Newly reported & unconfirmed
observations of Hydrogen & Oxygen
at south pole only at apojove
•  Geyser/Volcano - 7tons ~200km high
at ~1km/sec
Life on Europa??
•  As much liquid water as Earth
•  Europa seems to have a tidally
heated ocean
•  Maybe Black Smoker type life
forms????
•  JUICE ESA launch 2022, orbit
2030, ice penetrating RADAR
Io
•  Io-Jupiter distance same as Moon-Earth, but period=1.8days
•  Size &density ~Moon; no impact craters! =youngest surface
•  Io plasma torus: doughnut of volcanic ejecta swept up by
Jupiter’s magnetic field surrounds Jupiter in Io’s orbit;
lethal to people &probes
100 Volcanoes on Io
•  Hot interior from tidal heating
•  Sulfur in volcanic ejecta color
surface white, black & yellow
•  Prometheus has been erupting
for 18 years (since Voyager I)
Lava on Io
•  Temperature of some of Io’s
lava is hotter than Earth’s
•  Lava is enriched in
magnesium and iron
•  Infrared photo of Jupiter &
Io shows red spot in white &
lava below volcanic plume
Juno = Jupiter’s Wife
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Launched 2011-Arrival 2016
Oxygen isotopes= formation
Polar orbit studies
Aurora
Size of rocky core:
Core-accretion or
Gravitational Instability
Jupiter’s moon Io is very hot because:
a)  It has so many volcanoes
b)  It has not had time to cool since its formation
c)  Of impacts from the dust in the plasma torus
d)  Electric currents generated by its motion
through Jupiter’s magnetic field
e)  Orbital resonances with Europa and Ganymede
cause tidal heating
Geological Map of Ganymede