The Jovian Planets,The Jovian Planets,Part IPart I

Jupiter

JUPITERJUPITERThe God Of Thunder and SkyThe God Of Thunder and Sky

Physical DataPhysical Data

Diameter: 71,400 km (11.19 Dearth) Mass: 1.899x1030 g (317.9 Mearth) Density: 1.33 g/cm3 Rotation Period: 9.92 hours (radio) Tilt of Axis: 3o

Surface Temperature: 130 K

Physical DataPhysical Data

Orbital Semi-Major Axis: 5.203 AU Orbital Period: 11.86 years Orbital Inclination: 1.3o

Orbital Eccentricity: 0.048 Surface Gravity: 2.53 Earth gravity Satellites: 63 as of 2011 Magnetic Field: 19,000 times greater than

Earth’s

Jupiter’s InteriorJupiter’s Interior

METALLICHYDROGEN

IRONSILICATE

CORE

ATMOSPHERELIQUID

MOLECULAR HYDROGEN

Jupiter’s AtmosphereJupiter’s Atmosphere

90% Hydrogen 10% Helium Small amounts of:

MethaneAmmoniaEthaneWater

Jupiter’s AtmosphereJupiter’s AtmosphereClouds composed of: Ammonia Ammonia Hydrosulfide Hydrogen Sulfide Water Vapor

The Surface Temp.is 150 K (-190oF).

Jupiter’s AtmosphereJupiter’s Atmosphere

Usually brown or red Low-pressure regions of

sinking gas Lower than zonesZONES: Usually yellow-white High-pressure regions of

rising gas Higher than beltsJET STREAMS blow at the

boundaries

LH

H

H

L

L

L

BELTS:

Jupiter’s AtmosphereJupiter’s Atmosphere

Huge anti-cyclone (goes counterclockwise in Southern Hemisphere)

Circulation Period: 6 days Known for 300 years It is 14,000 km wide and

40,000 km (three Earth diameters!) long

The Great Red Spot

Jupiter’s AtmosphereJupiter’s Atmosphere

Hot Surface Temperature: The temperature at Jupiter’s surface (cloud

tops) is about 130 K Calculations say it should be 107 K Discrepancy because Jupiter’s interior radiates

2.5x as much heat as it receives from the Sun Jupiter is still slowly contracting

Jupiter’s Magnetic FieldJupiter’s Magnetic Field

Strongest magnetic field in the solar system Tilted 15o from the axis of rotation Highly flattened due to rapid rotation Distorted The moon Io, revolves

in the magnetosphere, and matter from it accumulates in a torus

Jupiter’s Magnetic FieldJupiter’s Magnetic Field

Matter in the Io torus stimulates the emission of radio bursts

This radiation called decametric radiation

Decametric bursts can be short (S-bursts) or long (L-bursts)

L-burst

S-Burst

S-Burst (slowed down)

Jupiter’s Rotation PeriodsJupiter’s Rotation Periods

Jupiter is a differential rotator This means not all parts of Jupiter’s surface

rotate at the same rate Equatorial rotation rate

(System I) = 9h50m30.003s

Polar rotation rate (System II) = 9h55m40.632s

Jupiter’s Rotation PeriodsJupiter’s Rotation Periods

The most widely used rotation period is System III

This is the rate at which the interior rotates as observed through the radio emissions

Radio rotation rate (System III) = 9h55m30.003s

Jupiter’s RingsJupiter’s Rings

Found by Voyager I fly-by

Main ring extends from 1.72-1.81 Jupiter radii from center of planet

Brightest part is about 6,000 km wide

Jupiter’s MoonsJupiter’s Moons At least 16 The four largest were discovered by Galileo and

are now referred to as the “Galilean Satellites”:Io, Europa, Ganymede, Callisto“I Eat Green Centipedes”: How to remember their order and relative density(i.e. Io is closest and most dense)

Jupiter’s MoonsJupiter’s MoonsIO EUROPA

GANYMEDE CALLISTO

size ofour Moon

size ofMercury

Jupiter’s MoonsJupiter’s MoonsIO EUROPA

GANYMEDE CALLISTO

active sulfurcrust

moltensilicate

densecore

ice/rockcrust

rockyinterior dense

core

subsurfaceoceans?

ice/rockcrust

water/icemantle

rocky ormuddy

core

thickice/rock

crust

rocky ormuddy

core

Jupiter’s MoonsJupiter’s Moons

IO Densest Galilean moon Most volcanically active

body in the Solar System Fresh surface, no impact

craters Inside Jupiter’s

magnetosphere: decametric emission

Jupiter’s MoonsJupiter’s Moons

Europa Very little surface

relief Smoothest body in the

Solar System Cracked ice surface

features

Jupiter’s MoonsJupiter’s Moons

Ganymede Largest moon in the

Solar System Surface is “Moon-

like”, i.e. cratered and has maria

Made of 50% water Little surface relief

Jupiter’s MoonsJupiter’s Moons

Callisto Perhaps the most

heavily cratered body in the Solar System

Lowest density of all the Galilean satellites (more than 50% water ice)

Little surface relief