lesson
Tilt changes sunlight angle and day length
1 · Learn
Earth's axis is tilted relative to its orbital plane. As Earth orbits the Sun, each hemisphere has changing day lengths and sunlight angles. This explains opposite seasonal patterns between the hemispheres.
Seasons are not explained simply by Earth being closer to the Sun. Never look directly at the Sun; use diagrams or approved indirect models.
2 · Worked example
When the Northern Hemisphere is tilted towards the Sun, it generally has longer days and more direct sunlight than in its winter.
3 · Your turn
Why would a distance-only explanation struggle to explain opposite seasons in the two hemispheres?
Check your answer
Both hemispheres are on the same Earth at essentially the same Earth-Sun distance, yet their seasonal patterns differ.
4 · Apply your learning
Use a globe-and-diagram model to compare hemispheres while keeping the axis direction consistent.
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Check a calculation · Year 5 onward
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Powers, roots and trigonometry · Year 7 onward
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