Page 79 - DK Children's Encyclopedia

Day and night SEE ALSO

▸ ▸ Earth p.83
▸ ▸ Light p.147
Day and night are times of light and darkness that ▸ ▸ Moon p.171
occur because the Earth spins, or rotates. One full ▸ ▸ Seasons p.221
day-and-night cycle is called a “day” for short. The half ▸ ▸ Solar system p.233

of the spinning Earth that faces the sun has daylight, ▸ ▸ Sun p.247
and the half facing away from the sun is in darkness. ▸ ▸ Tides p.254

Earth spins on
What makes its axis, which is
day and night? an imaginary line
that goes through
As the Earth spins round, the North and
parts of it move in and out South poles. The sun is where
of the sun’s light. The Earth’s light and
light parts are in day heat come from.
and the dark parts
are in night.

It takes the Earth
24 hours to make
one rotation.

The Earth
Light from used to spin
the sun much faster in the
distant past, and the
Half of the Earth Half of the
is in darkness. Earth is in light. days were much
shorter.

Eclipses
The moon circles the
Earth. Occasionally, it
blocks our view of the
sun during the day, and
the sky darkens for a
few minutes. This event
is called a solar eclipse.
Moving sun If the moon blocks all of
the sun, it is called a
The sun appears to move across the sky during the day total eclipse, and stars
as the Earth spins around it. It rises in the east and sets can be seen in the sky.
in the west. In the summer, the sun is higher in the sky Total eclipse
than in the winter.

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