1. The Earth – Sun Relationship

2. Core Content SC-04-2.3.4 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. 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.

3. Objective Be able to explain patterns that occur within the Earth-sun system. Be able to explain patterns that occur within the Earth-sun system.

4. Essential Question How can we determine patterns/relationships within the Earth-sun system using models? How can we determine patterns/relationships within the Earth-sun system using models?

5. Vocabulary Rotation – describes the way earth spins on its axis (causes day and night). Rotation – describes the way earth spins on its axis (causes day and night). Revolution – describes how earth circles the sun (takes 1 year). Revolution – describes how earth circles the sun (takes 1 year). Axis – an imaginary line that runs between earth’s north and south poles Axis – an imaginary line that runs between earth’s north and south poles

6. Earth’s Rotation Earth spins on its axis like a top. Earth spins on its axis like a top. It takes one full day for earth to make one full spin on its axis. It takes one full day for earth to make one full spin on its axis. This causes day and night. This causes day and night. Explains why the sun and other stars appear to move across the sky. Explains why the sun and other stars appear to move across the sky.

7. Earth’s Tilt Earth’s Axis is tilted 23 ½ degrees. Earth’s Axis is tilted 23 ½ degrees. If Earth’s axis was upright, our days would always be the same length and we would have no seasons. 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 tilt causes the seasons and longer or shorter days.

8. Earth’s Revolution All planets orbit the sun because of gravitational pull. All planets orbit the sun because of gravitational pull. Earth’s orbit around the sun is called its revolution. Earth’s orbit around the sun is called its revolution. Earth’s orbit is elliptical, not circular. Earth’s orbit is elliptical, not circular. As earth revolves around the sun, the seasons change. As earth revolves around the sun, the seasons change. It takes earth 365 days (or 1 year) to revolve the sun once. It takes earth 365 days (or 1 year) to revolve the sun once.

9. The Earth/Sun System

10. Earth’s Revolution

11. Today’s ticket out the door… What is rotation? What is rotation? What is revolution? What is revolution? What would happen if earth was not tilted on its axis? What would happen if earth was not tilted on its axis? Describe what causes day and night. Describe what causes day and night. Explain why seasons change. Explain why seasons change.