In this Grade 5 lesson from Science: A Closer Look, Chapter 5: The Universe, students explore how gravity and inertia work together to keep Earth in its elliptical orbit around the Sun. Students learn key concepts including revolution, rotation, insolation, and air pressure, while investigating how Earth's distance from the Sun affects gravitational pull. A hands-on inquiry activity models orbital motion to help students understand why Earth stays in its path rather than flying off into space or falling into the Sun.
Section 1
Gravity and Inertia Keep Earth Orbiting
Earth maintains its orbit around the Sun because of two forces working together: gravity pulls Earth toward the Sun while inertia keeps Earth moving forward in a nearly circular path called an ellipse.
Section 2
Earth's Tilt Creates Seasonal Changes
Earth's axis tilts about 23° and always points in the same direction as it orbits. This causes sunlight to hit different parts of Earth at different angles throughout the year, creating seasons.
Section 3
Sunlight Warms Earth Unevenly
The Sun's energy (insolation) hits Earth's spherical surface at different angles. Areas near the equator receive more concentrated heat energy than regions closer to the poles, causing temperature variations.
Section 4
Earth's Rotation Produces Day and Night
Earth completes one rotation on its axis every 24 hours, spinning from west to east. This rotation causes half of Earth to face the Sun (experiencing daylight) while the other half faces away (experiencing night).
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Section 1
Gravity and Inertia Keep Earth Orbiting
Earth maintains its orbit around the Sun because of two forces working together: gravity pulls Earth toward the Sun while inertia keeps Earth moving forward in a nearly circular path called an ellipse.
Section 2
Earth's Tilt Creates Seasonal Changes
Earth's axis tilts about 23° and always points in the same direction as it orbits. This causes sunlight to hit different parts of Earth at different angles throughout the year, creating seasons.
Section 3
Sunlight Warms Earth Unevenly
The Sun's energy (insolation) hits Earth's spherical surface at different angles. Areas near the equator receive more concentrated heat energy than regions closer to the poles, causing temperature variations.
Section 4
Earth's Rotation Produces Day and Night
Earth completes one rotation on its axis every 24 hours, spinning from west to east. This rotation causes half of Earth to face the Sun (experiencing daylight) while the other half faces away (experiencing night).
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter