Key Idea.
Section 1
Phases are Viewing Angles
Moon Phases are strictly a result of our changing perspective. A "phase" is simply a measure of how much of the Moon's illuminated half is visible from Earth.
Section 2
Synchronized Rotation
As the Moon orbits Earth, it rotates on its axis at the exact same speed. This synchronization means the same side of the Moon always faces Earth.
We never see the "far side" of the Moon. All the phases we observe happen on the surface of the "near side" as the sunlight sweeps across it.
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Section 1
Phases are Viewing Angles
Moon Phases are strictly a result of our changing perspective. A "phase" is simply a measure of how much of the Moon's illuminated half is visible from Earth.
Section 2
Synchronized Rotation
As the Moon orbits Earth, it rotates on its axis at the exact same speed. This synchronization means the same side of the Moon always faces Earth.
We never see the "far side" of the Moon. All the phases we observe happen on the surface of the "near side" as the sunlight sweeps across it.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter