Chapter 27
The Solar System
Standards
1a. Students know how the differences and similarities among the sun, the
terrestrial planets, and the gas planets may have been established during
the formation of the solar system.
1b. Students know the evidence from Earth and moon rocks indicates that
the solar system was formed from a nebular cloud of dust and gas approx.
4.6 billion years ago.
1c. Students know the evidence from geological studies of Earth and other
planets suggest that the early Earth was very different from Earth today.
Objective 1
Explain nebular hypothesis.
Objective 2
Assessment
Describe the land, atmosphere,
and oceans of early Earth.
Identify the basic characteristics
of the inner planets.
Identify the basic characteristics
of the outer planets.
Ch.27 Test
Review
Daily Bellwork, Science Starters
Objective 3
Objective 4
Vocabulary
Create flashcards for the following key terms.
They begin on page 685.
• Solar System
• Planet
• Solar Nebula
• Terrestrial Planet
• Gas Giant
• Kuiper Belt
INTERACTIVE The Planets Song
Create a Mnemonic to Remember the order of the
planets…
Example:
My
Very
Eager
Mother
Just
Served
Us
Noodles
Solar System Song
Brainpop Solar System
Formation of the Solar System
Nebular Hypothesis
• The sun and the planets formed at the same
time from a rotating cloud of dust and gas
called a NEBULA.
• Gravity pulled the gas and dust closer and
closer together creating heat and density.
• When the temp. became hot enough (10
million degrees) a star was born—our sun.
• 99% of all the matter in the nebula is in the
sun.
Nebular Hypothesis Cont.
• While the sun was forming in the center,
PLANETESIMALS were forming in the outer
regions.
• PLANETESIMALS were small bodies or ‘chunks’ of
debris that collided with other planetesimals
which eventually (through gravity and collisions)
formed larger bodies called PROTOPLANETS.
• PROTOPLANETS became PLANETS as they got
larger.
Formation of the Solar System Video Clip
Formation of the Inner Planets
• How the new planets developed depended on
their distance from the Sun.
• Those near the sun (Mercury, Venus, Earth, and
Mars) contained heavy elements (iron and nickel)
and they lost most of their gases (gravity was not
strong enough to hold them in).
• Denser material sank to center of planets and
layers formed.
• Inner planets are closest to the sun, dense, and
relatively small.
Formation of the Outer Planets
• Jupiter, Saturn, Uranus, and Neptune were far
from the sun and formed in cold areas where
they did not lose their gases (helium and
hydrogen) or their ices ( water, methane ice,
ammonia ice).
• Ices would later melt and the outer planets
are composed mainly of liquids and gases.
Ancient Earth
• Originally VERY hot
• Denser materials (iron) sank to center, formed 3
distinct layers (core, mantle, crust)
• Early atmosphere=lots of volcanoes outgassing
Nitrogen, water vapor, ammonia, methane,
argon, sulfur dioxide, carbon dioxide
• NO OXYGEN in the early atmosphere
• Early organisms began to photosynthesize which
led to the production of Oxygen…2 billion years
ago Oxygen level significantly increased and our
atmosphere became like it is today.
Earth’s formation Clips
Earth’s formation Clips
Inner Planets Today
• “Terrestrial” planets—made of solid rock with
metallic cores
• Many impact meteor craters
Mercury
•
•
•
•
•
Closest to the sun
Rotates on its axis every 59 days
Heavily cratered
Cliffs
Little atmosphere causes high temps in
daylight (472 degrees C) and low temps in
night (-173 degrees C)
Mercury
Venus
•
•
•
•
2nd planet from the sun
Slow rotation…once every 243 days
Earth’s ‘twin’…same size, mass, density
Atmosphere: 90 times the pressure of Earth,
96% carbon dioxide
• The CO2 creates a huge Greenhouse Effect,
creating temps of 464 degrees Celsius.
• Hottest planet in solar system
Venus
• Rocky surface, granite and basalt
• Mountains, volcanoes, lava plains, sand dunes
Venus
Mars
• 4th planet from the sun
• Rotates every 24 hours, 37 min, revolves around
sun in 687 days
• Axis tilts like Earth, has seasons
• Large volcanoes, seismic activity (marsquakes)
• Once had lots of water…now only in polar ice
caps, possibly underground
• Very thin atmosphere…temps range from 20 to
minus 130 degrees Celsius
Mars
Inner Planets Video
Outer Planets Today
• Separated from inner planets by the asteroid
belt.
• Also known as the Gas Giants
• Their large size led to greater gravity which let
them keep all their gases (unlike the inner
planets) and they have thick atmospheres
• Cores are rock and metal
• All four gas giants have ring systems
Jupiter
•
•
•
•
•
•
5th planet from the sun
Largest Planet
At least 60 moons, several thin rings
Atmosphere= 92% hydrogen and helium
Temp. is -160 degrees in the atmosphere
Lightning storms and thunderstorms (larger than on
Earth)
• Great Red Spot = a giant (2x the size of planet Earth),
rotating storm similar to a hurricane
• Jupiter’s interior is very hot…30,000 degrees! Mostly a
liquid planet
Jupiter
Saturn
• 6th planet from the sun
• Orbits the sun ever 29.5 years
• Very cold planet due to its distance from the sun
(-176 degrees)
• 30+moons
• Mostly hydrogen and helium with a rocky core
• Least dense planet in the solar system
• Complex ring system from comets and other
space debris
Saturn
Uranus
•
•
•
•
•
7th planet from the sun
3rd largest
At least 24 moons and 11 thin rings
Revolves around the sun in 84 years
Instead of rotating perpendicular to its orbit, it
rotates parallel every 17 hours
• Atmosphere is mostly hydrogen and helium and
methane. Blue color comes from methane gas
• Cold planet…-214 degrees, but could be higher
under all the clouds
Uranus
Neptune
• 8th planet from the sun, similar to Uranus in
size and mass
• 164 years to revolve around sun, rotates in 16
hours
• Atmosphere—Hydrogen, helium, methane
• Strongest winds in the solar system (1000
km/h)
Neptune
The Outer Planets Video
Solar System Song
INTERACTIVE/Assessment
Compare and Contrast the Inner and Outer
Planets…
Inner
Outer
INTERACTIVE/Assessment
Using your Venn Diagram as a guide, write an
essay comparing Inner and outer planets.
--Intro Paragraph
--Inner
--Outer
Minimum of 200 words
INTERACTIVE/Assessment
In groups you will create a poster for your planet. You need to
include:
• Drawing of planet
• 7 or more facts about your planet
–
–
–
–
–
–
–
–
–
Where in the solar system is it?
How big?
Moons?
Rings?
Atmosphere?
Rotates?
Revolves?
Temperature?
Other