Earth's tilt (23.5°) gives us seasons. The hemisphere tilted toward the Sun gets summer; the other gets winter.
Quick check
What actually causes Earth's seasons?
Opposite hemispheres, opposite seasons
When the Northern Hemisphere tilts toward the Sun, it gets longer days and more direct sunlight — summer. At the same moment the Southern Hemisphere tilts away — winter. Six months later it flips.
Four turning points
- Summer solstice — longest day
- Winter solstice — shortest day
- Spring & autumn equinoxes — day and night roughly equal
- Near the equator there's little seasonal change — just wet and dry seasons.
On the solstice, the Sun reaches its highest or lowest noon point of the year. 'Solstice' literally means 'sun stands still' — its daily climb seems to pause.