The document discusses day and night on Earth and the causes of seasons. It explains that the Earth's rotation on its axis causes day and night, with the side facing the sun experiencing day and the other side experiencing night. It also notes that the Earth is tilted on its axis and revolves around the sun, and that this tilt is what causes the seasons by changing how much sunlight different parts of the Earth receive throughout the year.

1. Sunday, September 7th
, 2008
SPACE
Day/Night and Seasons

2. Day and Night
 We have day and
night on Earth
because of the
Earth’s rotation – the
earth spinning around
and around. (1670
km/hr)

3.  The side of the earth
facing the sun is in
daylight.
 The other side of the
earth experiences
night.

4.  As the earth rotates,
everyone on earth
experiences day and
night.
 It takes 24 hours for
the Earth to rotate
once.

5. Seasons
 If the Earth was
perfectly balanced, as
it is in this animation,
we wouldn’t have
different seasons and
the sun would always
rise and set at the
same time every day.

6. Seasons
 Every part of the
Earth would receive
an equal amount of
sunlight as the earth
rotated.

7.  But the Earth isn’t
perfectly balanced,
it’s tilted on its axis…

8. …and it’s revolving around the sun.

9.  The tilt changes how
much sunlight each
part of the earth
receives.
 It is this tilt which
makes our days
longer or shorter and
it’s what causes the
seasons.

10.  In the summer, we’re
tilted towards the sun.
 Our days are longer
and we receive more
direct sunlight (which
makes it hot).

11.  In winter, we’re tilted
away from the sun.
 Our days are shorter
and we receive less
direct sunlight (which
makes it cold)

12.  Animation  Video  Seasons Game

13. Time and movement of earth and
moon around sun
 Animation