2. EARTH’S ROTATION AND REVOLUTION

3. EARTH’S SEASONS Sunlight on Earth
The diagram shows how Earth’s tilted axis affects the strength of sunlight in different places.

4. EARTH’S SEASONS Seasons
The diagram shows how Earth moves during the year.

5. EARTH’S SEASONS WINTER SUMMER

6. EARTH’S SEASONS

7. Seasons Interactive Display
EARTH’S SEASONS
Solstices and Equinoxes
The diagrams show the apparent path of the sun at the solstices and equinoxes in the Northern Hemisphere. What is the sun’s path at the equinoxes and the December solstice for the Southern Hemisphere?
Seasons Interactive Display

8. EARTH’S SEASONS

9. MOON’S PHASES The Moon’s Motion

10. MOON’S PHASES Moon Phases
As the moon orbits Earth, its sunlit side is seen from different angles.

11. MOON’S PHASES

12. SOLAR ECLIPSES Solar Eclipse
The diagram shows the moon’s penumbra and umbra during an eclipse.

13. LUNAR ECLIPSES Lunar Eclipse
As the moon moves through Earth’s shadow, total and partial eclipses occur.

14. Tides
Tide Cycle
Tides are caused mainly by differences in how much gravity from the moon and the sun pulls on different parts of Earth.