Weather on Jupiter
Belts and Zones
differential Rotation
Images from Cassini
(Fast) Differential Rotation!!
300-500 km/hr
Causes a lot of WEATHER!
Weather on Jupiter
Differential Rotation:
Speed different @
different latitudes
Belts and Zones
Caused by Convection +
Differential rotation
ESO-VLT
Weather on Earth
Differential Rotation:
Speed different @
different latitudes
Belts and Zones
Caused by Convection +
Differential rotation
Weather on Earth
Differential Rotation:
Speed different @
different latitudes
Belts and Zones
Caused by Convection +
Differential rotation
Weather on Earth
Differential Rotation:
Speed different @
different latitudes
Belts and Zones
Caused by Convection +
Differential rotation
Weather on Earth
Differential Rotation:
Speed different @
different latitudes
Belts and Zones
Caused by Convection +
Differential rotation
Uranus & Neptune - Discovery
• Only 6 Planets known until 18th C.
• William Herschel discovers a “comet”, March 13, 1781
Uranus was
discovered by
accident!
• Messier: Not Fuzzy enough . . . Welcome URANUS!
Uranus & Neptune - Discovery
• Galileo found Neptune by accident but didn’t know it!
Neptune was
discovered
on purpose!
Uranus & Neptune - Discovery
Existence of
Neptune was
predicted
before
detection why??
• Neptune was
discovered on
September 23,
1846
Neptune was
discovered
on purpose!
Uranus & Neptune - Ice Giants
Orbital Period - 85 years
Rotation Period - 17 hours
Orbital Distance - 19 AU
Mass - 14.5 Earth Masses
Density - 1.4 g/cc
Neptune
Uranus
Orbital Period - 165 years
Rotation Period - 16 hours
Orbital Distance - 30 AU
Mass - 17 Earth Masses
Density - 1.6 g/cc
Images from Voyager
Structure of Gas Giants
Uranus & Neptune - Ice Giants
Atmospheres of H/He &
Methane
Mantles of liquid/icy water,
ammonia, & methane
small rocky/icy Cores
(No Liquid Metallic Hydrogen...)
Why not?
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Jovian Planets: Masses & Sizes
Planet
Mass
(kg)
Jupiter
Mass
(Earth
masses)
Radius
(km)
Radius
(Earth Radii)
1.898 x 1027 317.7
71,492
11.2
Saturn
5.69 x 1026
95.2
60,268
9.4
Uranus
8.682 x 1025 14.5
25,559
4.0
Neptune
1.024 x 1026 17.1
24,764
3.9
Uranus/Neptune - Magnetic Fields
How?
U
Uranus/Neptune - Magnetic Fields
How?
Probably generated in
Icy Mantle
Fields are off-center
& Unstable!
U
Uranus & Neptune in Infrared
-no internal heat
source (Uranus)
-weaker internal
heat source
(Neptune)
Which Planet
should have more
weather?
IR Images from
Keck/Palomar
U
Uranus & Neptune - Weather
Which Planet should have more weather?
U: Relatively Featureless
N: Circulation & Weather!
U
Uranus & Neptune - Weather
Which Planet should have more weather?
Liquid Methane Clouds
U: Relatively Featureless
N: Circulation & Weather!
U
Neptune - The Great Dark Spot
winds up to 1500 km/hr!
Voyager - 1989
Spot is size of Earth!
Changed over 36 hours!
U
Neptune - The Great Dark Spot
GONE!!
U
Uranus - Obliquity
Obliquity = 98 degrees!
Seasons are 20 years long!
(Neptune is more reasonable at 29.6 deg.)
U
Obliquity of Planets
Obliquity = 98 degrees!
Seasons are 20 years long!
U
Uranus - Rings
U
Uranus - Rings
U
Neptune - Rings
U
Moons of Ice Giants
(HST-Uranus & Ariel)
U
Moons of Ice Giants
Uranus - 27 known
Images fr.Voyager 2
Neptune - 13 (including Triton)
U
Uranus & Neptune
Universe Video
U