Transcript A Tour through the Solar System - iPad-Space

A Tour through the
Solar System
The Inner Planets
Include Mercury, Venus, Earth,
and Mars
 Also known as terrestrial planets
(terra means earth in Latin)
 All terrestrial planets are small,
dense, and have rocky surfaces.
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Mercury
Named for the Roman messenger god
(Greek - Hermes)
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Smallest terrestrial
planet (diameter is
4,879 km)
Surface is covered
by plains and craters
Has no atmosphere
and no moons
Has the greatest
temperature range
of any of the
planets: Day: 430°C
Night: - 170°C
Venus
Named for the Roman goddess of love and beauty
(Greek - Aphrodite)
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Close to the size of earth (Diameter is 12,104
km)
Surface is very volcanic and has many plains
covered in flowing lava
Atmosphere is so thick it is considered one
giant cloud. The air pressure is 90 times
earth’s. Air is mostly carbon dioxide.
Atmosphere traps in enough heat to melt lead
(460°C), making it the hottest planet).
No moons
Venus takes longer to rotate on its axis than it
does to revolve around the sun. This makes its
day longer than its year.
Earth
Only Planet Name Not Derived from Mythology
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Diameter is 12,756 km
Only planet that has
liquid water on the
surface. The surface
is solid rock with
many volcanoes
Only atmosphere rich
in oxygen (20%) Most
of the rest of the
atmosphere is
nitrogen
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Has 1 moon
commonly called
moon, but also
referred to as Luna
(Roman goddess of
the moon)
Is in the exact
position in the solar
system needed to
support life. Any
closer to the sun and
it would be to hot;
farther, too cold
Mars
Named for the Roman god of war
(Greek – Ares)
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Diameter – 6,794 km
Surface is red because of rich amounts
of iron in the rocks. There are icecaps
at the poles. Many volcanoes dot the
surface but none are active.
Atmosphere is 95% carbon dioxide.
2 moons (Phobos and Diemos)
Mars has a tilted axis and has seasons.
Its largest volcano, Olympus Mons is
the size of Missouri and is 3 times
taller than Mt. Everest.
The Outer Planets
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Include Jupiter, Saturn, Uranus, and
Neptune
Also known as the gas giants.
Don’t have solid surfaces.
Have a set of discs of small particles
of ice and rock called rings
Jupiter
Named for the Roman king of the gods
(Greek – Zeus)
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Largest planet
(Diameter – 143,000
km)
Surface is gaseous.
Atmosphere made up
of mostly hydrogen
and helium. The
Great Red Spot (GRS)
is a storm twice as
large as Earth.
Storms on Jupiter
never end. GRS first
observed in the mid1600’s.
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Rings are barely
noticeable.
63 known moons; Io,
Europa, Ganymede,
and Callisto are the
largest and were
discovered by Galileo
Its mass is 2.5 times
that of all the rest of
the planets.
Io
Europa
Callisto
Ganymede
Saturn
Named for the Roman god of agriculture
(Zeus’ father) (Greek – Cronus/Kronos)
 2nd largest (Diameter – 120,500 km)
 Gaseous surface
 Atmosphere is primarily hydrogen and
helium. Also has clouds and storms
 Rings are 250,000 km in diameter, but
only 1 km thick.
 34 known moons, Titan is the largest
 Saturn’s density is less than water.
Uranus
Named for the Greek god of the heavens
(Chronus’ father, husband of Gaia)
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Diameter – 51,100 km
Gaseous surface
Traces of methane in
the atmosphere give
it the blue-green
color
Rings go from north
to south
At least 25 moons,
names come from
writings of
Shakespeare and
Alexander Pope
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Uranus’ axis is tilted
90°. This causes a
“north/south”
rotation instead of
the normal
“east/west” rotation.
Neptune
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Named for Roman god of the sea
(Greek – Poseidon)
Diameter – 49,500 km
Gaseous surface
Blue gases fill the atmosphere. White
and dark-colored clouds dot the sky.
Rings are barely noticeable.
13 moons, largest is named Triton.
Neptune had a huge storm called the
Great Dark spot, but it didn’t last.
The planet is actually sinking, causing
the core to heat up, which results in
clouds.
Why Pluto Isn’t a Planet
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1.
2.
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It doesn’t meet the third part of the
definition of a planet:
Must orbit around the sun
Must have a nearly round shape
Must have cleared the area around it
so that no competing celestial bodies
are around (Charon is a competing
body that wasn’t cleared)
Pluto
Named for the Roman god of the underworld
(Greek – Hades)
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Diameter – 2,400 km,
smaller than the
moon, Io, Europa,
Ganymede, Callisto,
Titan, and Triton
Rocky surface
No atmosphere
1 moon – Charon
(Greek figure who
ferried people to the
underworld)
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Orbit lasts 248 earth
years.
At times during the
orbit Pluto is actually
closer to the sun than
Neptune.
As of August 24, 2006
Pluto is considered a
“dwarf planet.”
Other Dwarf Planets
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Eris – largest dwarf
planet, has 1 moon
(Dysnomia)
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Located in the Kuiper Belt
(Out past Pluto)
Ceres – smallest dwarf
planet
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Located in the asteroid
belt (between Mars and
Jupiter)
Other Dwarf Planets
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MakeMake was named a dwarf
planet in June of 2008.
It’s the 3rd largest dwarf planet.
 It is located in the Kuiper Belt, where
Eris is located.
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Haumea
It’s the 4th largest dwarf planet.
 2 moons – Hi’iaka and Namaka
 Located in the Kuiper Belt
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