The Earth – Sun Relationship
Core Content
• SC-04-2.3.4
• Students will identify patterns, recognize
relationships and draw conclusions about
the Earth-Sun system by interpreting a
variety of representations/models (e.g.,
diagrams, sundials, distance of sun above
horizon) of the sun’s apparent movement
in the sky.
Objective
• Be able to explain patterns that occur
within the Earth-sun system.
Essential Question
• How can we determine
patterns/relationships within the Earth-sun
system using models?
Vocabulary
• Rotation – describes the way earth spins
on its axis (causes day and night).
• Revolution – describes how earth circles
the sun (takes 1 year).
• Axis – an imaginary line that runs between
earth’s north and south poles
Earth’s Rotation
• Earth spins on its axis like
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a top.
It takes one full day for
earth to make one full
spin on its axis.
This causes day and
night.
Explains why the sun and
other stars appear to
move across the sky.
Earth’s Tilt
• Earth’s Axis is tilted
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23 ½ degrees.
If Earth’s axis was
upright, our days
would always be the
same length and we
would have no
seasons.
Earth’s tilt causes the
seasons and longer or
shorter days.
Earth’s Revolution
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All planets orbit the sun because of gravitational pull.
Earth’s orbit around the sun is called its revolution.
Earth’s orbit is elliptical, not circular.
As earth revolves around the sun, the seasons change.
It takes earth 365 days (or 1 year) to revolve the sun
once.
The Earth/Sun System
Earth’s Revolution
Today’s ticket out the door…
• What is rotation?
• What is revolution?
• What would happen if earth was not tilted
on its axis?
• Describe what causes day and night.
• Explain why seasons change.