1. What causes seasons?
Explain your answer! Include a diagram
 Seasons are caused by Earth’s tilt and it’s revolution around
the sun.
 Different angles of rays strike different locations
 Different length of daylight can be experienced at different
locations.

2. What is the tilt of the Earth's axis (in
degrees)? What do you think caused it?
 Earth’s tilt is 23.5 degrees.
 Thought to be caused by a large asteroid that hit Earth,
broke off part of Earth and formed the moon.

3. During which season do the Sun’s rays hit the
northern hemisphere most directly? Explain.
 Summer, in June, when the most direct light strikes the T. of
Cancer, the Northern Hemisphere is tilted towards the sun
and receives the most direct sunlight .

4. During which season are the days the
shortest? How short? Why are they short?
 In the Northern Hemisphere...
 On the December (Winter) Solstice
 They are short because the Southern Hemisphere is facing the
sun while the Northern Hemisphere is facing away.
 More darkness about 15 hours – Less light about 9 hours.
 This means that the northern hemisphere rotates through more
darkness than daylight, making the day shorter.

5. During which season are the days the
longest? How long? Why are they long?
 In the Northern Hemisphere...
 On the June (Summer) Solstice
 They are long because the Northern Hemisphere is facing the
sun while the Southern Hemisphere is facing away.
 More day light about 15 hours – Less darkness about 9 hours.
 This means that the northern hemisphere rotates through more
daylight than darkness, making the day longer.

6. What is the name of the shortest
day of the year? When is it?
 In the Northern Hemisphere...
 December (Winter) Solstice
 December 21 or 22

7. What is the name of the longest
day of the year? When is it?
 In the Northern Hemisphere...
 June (Summer) Solstice
 June 21 or 22

8. What are the names of the two days in
which the day and night are of equal length?
 Autumnal (Fall) Equinox
 Vernal (Spring) Equinox

9. When do the two days
described in #8 occur?
 Autumnal (Fall) Equinox – September 21 or 22
 Vernal (Spring) Equinox – March 20 or 21

10. When it’s summer in the northern hemisphere,
what is it in the southern hemisphere, Why?
 When it is summer in the northern hemisphere, it is winter in the
southern hemisphere.
 This is because when the Northern hemisphere is facing the sun,
the Southern hemisphere is facing away from the sun, the light
then strikes the ground more indirect and is cooler in the
Southern Hemisphere.

11. How does Earth’s tilt
effect seasons?
 Earth’s tilt causes different angles of rays and length of days.
WINTER SPRING SUMMER FALL

12. Give evidence that seasons are not caused by
Earth being closer & farther from the sun.
 When Earth is closest to the sun, the northern hemisphere is
facing away from the sun and is experiencing winter.

13. On the first day of summer this year, how
many hours of sunlight will we have? Dark?
 We will have about…
 Daylight ~ 15 hrs.
 Darkness ~ 9hrs.

14. In just a few weeks winter will be here.
How many hours of light will we have? Dark?
 We will have about…
 Daylight ~ 9 hrs.
 Darkness ~ 15 hrs.

15. On Dec 20 or 21, where would the
sun’s most direct rays be located?
 The most direct rays will be located over the southern
hemisphere striking the Tropic of Capricorn.

16. How would seasons be effected if Earth were
tilted, but did not revolve around the sun?
 Every location on Earth would experience the same season
and would never change because the way the light strikes
Earth’s surface would not differ through out the year.

17. Why do the poles sometimes have extremely
long periods of all daylight or all darkness?
 The farther the latitude from the equator the more drastic and
extreme the daylight/darkness change.
 At the poles the sun moves parallel to the ground through the sky.
 During Winter, the sun stays below the horizon line and is not visible
in the sky, receiving 0 hours of daylight.
 During summer, the sun stays above the horizon line and is visible for
24 hours.

18. How does earth’s revolution effect seasons?
 When Earth revolves on its orbit the sun’s light will strike different
latitudes more directly (from Tropic of Cancer to Tropic of
Capricorn).
 Locations on Earth will receive different angles of rays throughout the
year.
 Locations on Earth will also receive different amounts of daylight
throughout the year.
WINTER SPRING SUMMER FALL