In this Grade 6 Earth Science lesson from Chapter 21, students learn to identify the types of objects in the solar system, compare the sizes and distances of planets from the Sun, and explore how the solar system formed. Key vocabulary includes astronomical unit (AU) and ellipse, which help students measure and describe planetary distances and orbits. Students also conduct a hands-on experiment modeling planet formation to understand how spinning matter gathers into clumps over time.
Section 1
Planets Orbit the Sun in Predictable Paths
Planets follow elliptical orbits around the Sun in the same direction. Most planets' orbits are nearly circular, with the inner planets clustered closer together than the widely spaced outer planets.
Section 2
Solar System Formed from Swirling Dust
Our solar system began as a giant cloud of gas and dust that flattened into a spinning disk. The center became the Sun, while smaller clumps of material stuck together to form planets, moons, asteroids, and comets.
Section 3
Gravity Shapes Objects in Space
When space objects grow large enough, their gravity pulls material equally from all sides, creating spherical shapes. Smaller objects like asteroids remain lumpy because they lack sufficient mass to reshape themselves.
Section 4
Astronomers Measure Vast Cosmic Distances
Scientists use the astronomical unit (AU)—Earth's average distance from the Sun (150 million kilometers)—to measure distances in our solar system, making incredibly large numbers more manageable.
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Section 1
Planets Orbit the Sun in Predictable Paths
Planets follow elliptical orbits around the Sun in the same direction. Most planets' orbits are nearly circular, with the inner planets clustered closer together than the widely spaced outer planets.
Section 2
Solar System Formed from Swirling Dust
Our solar system began as a giant cloud of gas and dust that flattened into a spinning disk. The center became the Sun, while smaller clumps of material stuck together to form planets, moons, asteroids, and comets.
Section 3
Gravity Shapes Objects in Space
When space objects grow large enough, their gravity pulls material equally from all sides, creating spherical shapes. Smaller objects like asteroids remain lumpy because they lack sufficient mass to reshape themselves.
Section 4
Astronomers Measure Vast Cosmic Distances
Scientists use the astronomical unit (AU)—Earth's average distance from the Sun (150 million kilometers)—to measure distances in our solar system, making incredibly large numbers more manageable.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter