Is the moon at position
A, B, C or D when it appears full?


The Sun, the Earth and the Moon.  Diagram not to scale.

You're right!

During a full moon, the sunlit side
of the Moon faces the Earth.

FYI: Moonlight is sunlight that has reflected off the Moon's surface and into your eyes. If the Sun's light were to go out, there would be no moonlight.

Try Again

This phase of the moon is at first-quarter. The lit portion appears as as a half-circle to viewers on Earth.

The next time you look at the moon in the night sky, imagine that the Sun must be in the direction of the light source.

Try Again

This is a new moon.
During a new moon, the dark side
of the moon faces the Earth.

Try Again

This phase of the moon is at third-quarter. The lit portion appears as as a half-circle to viewers on Earth.

The next time you look at the moon in the night sky, imagine that the Sun must be in the direction of the light source.
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Diagram: Images courtesy of NASA.
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