What You Need to Know

Earth spins around once every 24 hours

The side facing the Sun has daytime

The side facing away from the Sun has nighttime

The Sun appears to move across the sky during the day

Key Vocabulary

the time when the Sun lights up our part of Earth

the time when our part of Earth faces away from the Sun

to spin around a central point

a dark shape made when an object blocks light

Select the correct answer for each question. Click "Check Answer" to see if you are right.

Question 1

Why do we have night?

The Sun turns off Clouds block all sunlight The Moon covers the Sun Our part of Earth faces away from the Sun

Question 2

How long does it take Earth to spin around once?

24 hours 7 days 12 hours 1 year

Question 3

When is your shadow longest?

At midday when the Sun is high In the morning or evening when the Sun is low At night Shadows are always the same length