Download 4.5 The Outer Planets - Germantown School District

What Do the Outer Planets Have in Common?
What Are the Characteristics of Each Outer Planet?
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Large
Gas giants (no solid
surface)
Hydrogen and helium
Ices of ammonia and methane
Strong gravitational forces (due to their size)
keep these gases from escaping
 Much of the material in gas planets is actually
liquid because the pressure inside the planet is
so high
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 The outer layers are extremely cold
 Temperature increases inward with pressure
All outer planets have
many moons
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Jupiter: at least 63
Saturn: at least 61
Uranus: at least 27
Neptune: at least 13
All outer planets have rings
 Thin disks of small particles of ice and rock
 Saturn’s rings are largest and most complex
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Scientists are constantly discovering new
information about these planets and moons
(using telescopes and space probes)
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Largest and most
massive planet
Mass is 2 ½ times
more than all of
the other planets
combined
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Thick atmosphere
(hydrogen and
helium)
Great Red Spot:
Storm larger than
Earth!
 Similar to a hurricane
 Never ending
 20,000 km long and
12,000 km wide
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Dense core of rock and iron at its center
 Pressure is 30 times greater than on the surface
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It has a thick mantle of liquid hydrogen and
helium
 Jupiter’s largest moon. (Larger than Mercury)
 Surface has dark and bright areas
 Second largest
 Less ice
 Most craters
 Not icy
 May have 300
active volcanoes
 Ice
 Liquid water below the ice (possibly)
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2nd largest planet
Thick atmosphere
(hydrogen and
helium)
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Made up of chunks of ice and rock going
around Saturn
Some are kept in place from gravity of tiny
moons
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Titan (largest…larger than Mercury)
 Thick atmosphere (nitrogen and methane)
 Some features formed from flowing liquid
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Mimas and Tethys: craters and trenches
Enceladus: Ice and water erupt in geysers
Phoebe: ring of material found
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4 times
diameter of
Earth
Looks bluegreen due to
methane in
atmosphere
Rings
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The 5 largest moons have icy, cratered
surfaces
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Tilted at an angle of
about 90 degrees
from the vertical
The tilt is due to an
object hitting Uranus
and knocking it on its
side
Rotation = 17 hours
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Similar to Uranus
in size and color
Blue and cold
Atmosphere
contains visible
clouds
Interior is hot
(forming clouds
and storms at the
surface)
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Great Dark Spot
(about the size of
Earth)
 Scientists think it is
probably a giant
storm that lasted a
short period of time
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13 moons
Triton (largest)
Thin atmosphere
Nitrogen ice over south pole