1. Reasons for the Seasons
Page 83

2. Why do we have seasons on Earth?

3. Why do we have seasons on Earth?
The most common answer-and its wrong!- is that the earth is getting closer and farther from the sun.
THIS IS WRONG!!

5. It’s all about the angle of the light!

6. What is Direct Light? Light coming in straight at an object.
Concentrated in one area.
When the sun is directly overhead, we get Direct Light.

7. What is Indirect Light?
Light coming in at an angle. (Sometimes called “Angled Light”)
Spread out over an area.
When the sun is NOT directly overhead, we get Indirect Light.

8. Why are there seasons?

9. Which sunlight will be hotter?
Direct Light
Indirect Light

10. What shape is the Earth?
Will sunlight hit the earth at the same angle for the entire surface of the earth?

11. some parts of the earth’s surface receive direct light, others areas get indirect light.
The Earth is a sphere…

12. therefore- some areas will get HOT, direct light, others will get cooler indirect light.
The Earth is a sphere…

13. What else can we say about the Earth?
The earth is TILTED on its AXIS.

14. What is the Earth’s AXIS?
An imaginary line that runs through the middle of the Earth
The line which the Earth rotates/ spins around.

15. A tilted axis means…
The part of the earth that is receiving direct light changes throughout the year as the earth orbits the sun!

17. When do we have summer?
When our half of the Earth (Northern Hemisphere) is pointed towards the Sun

18. When our half (hemisphere) is pointed away from the sun
When do we have winter?
When our half (hemisphere) is pointed away from the sun

20. When is it the hottest?
When the sun is directly over us.

21. Notice the moon and the Earth’s
Revolutions are both counter clockwise

22. South of the equator the seasons are opposite of ours in the North

23. March 21
Dec. 21
June 21
Sept. 21

25. What is a SOLSTICE? The sun is directly over the Tropic of Cancer...
Summer
OR…
which means

26. The Sun over the Tropic of Capricorn– means winter

27. June 21 Sun is directly over Tropic of Cancer – our Longest Day Summer Solstice

28. What is an EQUINOX?
The sun is directly above the EQUATOR
EQUAL Night
EVERY Sept 22, March 22