Is there a dark side of the Moon?

No. There is no permanently dark side of the Moon. The far side, which we never see from Earth, gets as much sunlight as the near side; during a new moon, when our side looks dark, the far side is fully lit.

What's actually true

The Moon's far side gets as much sunlight as the near side. There is no permanently "dark side" of the Moon. Because the Moon spins once per orbit, we always see the same face, but the hidden far side has day and night like anywhere else. During a new moon, when our side looks dark, the far side is fully lit.

Takeaway: "Far side" is the accurate term; "dark side" is just a nickname.

Why people believe it

In this phrase 'dark' is best read as unknown rather than unlit: because the Moon always shows us the same face, the far side stayed hidden until spacecraft photographed it. Over time the word was read literally, and the phrase spread through films, music and science fiction. It also feels right because we always see the same face, so it is easy to imagine the other face being in permanent shadow, when in fact it has day and night like the near side.

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