Transcript The Inner Solar System • The four inner planets are all relatively small and dense, and have rocky surfaces. • The terrestrial planets are planets.

The Inner Solar System
• The four inner planets are all
relatively small and dense, and
have rocky surfaces.
• The terrestrial planets are
planets similar in structure to
Earth.
• Mercury, Venus, Earth, and
Mars are called the terrestrial
planets.
The Sun
• The sun’s energy is produced in
its central region by the fusion
of hydrogen nuclei into helium
nuclei.
• The sun remains stable because
the inward pull of gravity
balances the outward push of
thermal pressure from nuclear
fusion.
Nuclear_Fusion_Joins_Atoms
Nuclear_Fusion_Creates_New_Elements
The Sun’s Interior
•
•
•
•
The sun’s interior consists of the
core, the radiation zone, and the
convection zone.
Core – is the sun’s central region,
where nuclear fusion occurs.
Radiation Zone – is a region of
compressed gas. Energy is
transferred by the absorption and
reradiation of electromagnetic
waves.
Convection Zone – The outer layer
of the sun. energy is transferred
outwardly by convection currents.
The Sun’s Atmosphere
• Photosphere – the
innermost layer of the
sun’s atmosphere. It is the
visible surface.
• The photosphere is not a
solid, but it is considered
the surface.
• Astronomers can’t see
through the photosphere.
• The_Photosphere_and_t
he_Solar_Wind
The Sun’s Atmosphere
• Chromosphere – is the
middle layer of the sun’s
atmosphere.
• At high temperatures,
hydrogen emits a reddish
color.
• Chromosphere means
“sphere of color”
Corona
• The corona is the
outermost layer of the
sun’s atmosphere.
• The gases are thin at
this layer
• The chromosphere and
corona can only be
seen during solar
eclipses.
Stages of Solar Eclipse
• The corona can only
be seen from Earth
during a total solar
eclipse or when
viewed with a special
telescope.
Features of the Sun’s Atmosphere
• Sunspots – small dark
regions on the sun’s
surface.
• Sunspots are areas of
gas in the photosphere
that are cooler than the
surrounding gases.
• Sunspots give off less
energy
Other Features
• Prominences – occur near sunspots. They
are huge loops of gas that erupts.
• Solar Flares – the sun’s surface erupts
hurling charged particles into space
Review Concepts
•
•
•
•
•
•
•
•
•
What is the source of the sun’s energy?
Nuclear fusion in the sun’s core.
What two forces in the sun interact to produce a stable structure?
Gravity and the thermal pressure from fusion.
List the layers of the sun’s interior from the center outward and
describe each one.
Core: central region where fusion takes place; Radiation zone: middle
layer, energy is transferred by radiation;
convection zone: outer layer, energy is transferred by convection.
List the layers of the sun’s atmosphere
Photosphere, chromosphere, corona
List three features that exist on the sun’s surface.
•Sunspots, Prominences, and Solar flares
Debbie’s sun
Exploring_Space__The_Universe
Video_Quiz__The_Sun
__Our_Star_Attraction
Mercury
• Mercury is the smallest of the
terrestrial planets and the
closest planet to the sun.
• Mercury is a dense planet with
a very large iron core.
• Mercury is geologically dead.
• There is no mantle convection
within the planet and little
erosion on its surface.
Venus
• Venus’s thick atmosphere is
composed mostly of carbon
dioxide, which traps heat and
raises the planet’s temperature.
• Venus’s atmosphere contains
droplets of sulfuric acid.
• Average surface temperature
460 degrees.
Mars
• Mars is the most Earthlike of all of the
planets. The weathering of iron rock on its
surface gives the planet a reddish color.
This is why Mars is called the “Red Planet.”
Mars
Asteroids
• Beyond Mars is a region of
small, rocky bodies called
asteroids that orbit the sun.
• This region is referred as the
asteroid belt
• Scientist now hypothesize that
asteroids are remnants of the
early solar system that never
came together to form a planet