<p>Yes, the dark side of the moon is mostly hidden from earthbound observers. This is due to <a href="https://en.wikipedia.org/wiki/Tidal_locking" rel="nofollow noreferrer">tidal locking</a>:</p>

<blockquote>
  <p>A tidally locked body takes just as long to rotate around its own axis as it does to revolve around its partner. This causes one hemisphere constantly to face the partner body.</p>
</blockquote>

<p>In other words, one moon-year is just as long as one moon-day.</p>

<p>The left-hand side shows the actual configuration of earth and moon: The orbit is locked and we can only observe one side of the moon. On the (fictional) right-hand side, the moon does not rotate around itself and we can observe different areas of the moon at different times.</p>

<p><a href="https://i.sstatic.net/JclGv.gif" rel="nofollow noreferrer"><img src="https://i.sstatic.net/JclGv.gif" alt="Left: Tidally locked orbit. Right: Orbit without any spin."></a></p>

<p>I should note that we can actually observe not 50%, but around 59% of the moon's surface because of <a href="https://en.wikipedia.org/wiki/Libration" rel="nofollow noreferrer">libration</a> and parallax effects that cause the moon to slightly "wobble":
<a href="https://i.sstatic.net/wRTb2.gif" rel="nofollow noreferrer"><img src="https://i.sstatic.net/wRTb2.gif" alt="Simulated view of the moon, demonstrating librations."></a></p>

<p>You can find all those images and further explanation in the linked wikipedia articles on <a href="https://en.wikipedia.org/wiki/Tidal_locking" rel="nofollow noreferrer">tidal locking</a> and <a href="https://en.wikipedia.org/wiki/Libration" rel="nofollow noreferrer">libration</a>.</p>

CC BY-SA 3.0
2015-08-30T13:13:29.190Z
Read David Hammen's comment on the question, you are talking about the far side of the Moon **not** the Dark Side
Conrad Turner
CC BY-SA 3.0
2015-08-30T20:35:58.173Z
Yes, the question and my answer are about the far side. However, this side is typically referred to as [*dark side*](https://en.wikipedia.org/wiki/Far_side_of_the_Moon) even though it does get illuminated by the sun in periods of two weeks. I don't see what else the *dark side* could mean in this context.
Daniel Lenz
CC BY-SA 3.0
2015-08-30T22:03:38.953Z
Erroneously refered to as the dark side, you could try pointing this out
Conrad Turner
CC BY-SA 3.0
2015-08-28T09:38:27.197Z
2015-08-28T11:19:18.230Z
2015-08-28T11:19:18.230Z
Daniel Lenz
<p>I encountered this statement that the dark side of the moon is hidden from our sights.
Could someone please explain? </p>

CC BY-SA 3.0
2015-08-29T18:41:28.347Z
The dark side of the Moon is not hidden from our sight. When the Moon is nearly new, you can see a thin band of the Moon that is well lit, but you can also see the rest of the Moon. That is the dark side of the Moon. People regularly confuse the dark side of the Moon with the far side of the Moon. Most of the latter is hidden from our sight.
David Hammen
<the-moon><natural-satellites><satellite>
The dark side of the moon
Abhinav
# The dark side of the moon

(Asked by: username_0 on 2015-08-28)

I encountered this statement that the dark side of the moon is hidden from our sights.
Could someone please explain?

**Tags:** the-moon, natural-satellites, satellite

> **Comments:**
> **username_1**: The dark side of the Moon is not hidden from our sight. When the Moon is nearly new, you can see a thin band of the Moon that is well lit, but you can also see the rest of the Moon. That is the dark side of the Moon. People regularly confuse the dark side of the Moon with the far side of the Moon. Most of the latter is hidden from our sight.  

---

## 1 answers

### Answer by username_2 on 2015-08-28. Score: 7 | Accepted answer

Yes, the dark side of the moon is mostly hidden from earthbound observers. This is due to [tidal locking](https://en.wikipedia.org/wiki/Tidal_locking):

> A tidally locked body takes just as long to rotate around its own axis as it does to revolve around its partner. This causes one hemisphere constantly to face the partner body.

In other words, one moon-year is just as long as one moon-day.

The left-hand side shows the actual configuration of earth and moon: The orbit is locked and we can only observe one side of the moon. On the (fictional) right-hand side, the moon does not rotate around itself and we can observe different areas of the moon at different times.

[![Left: Tidally locked orbit. Right: Orbit without any spin.](https://i.sstatic.net/JclGv.gif)](https://i.sstatic.net/JclGv.gif)

I should note that we can actually observe not 50%, but around 59% of the moon's surface because of [libration](https://en.wikipedia.org/wiki/Libration) and parallax effects that cause the moon to slightly "wobble":
[![Simulated view of the moon, demonstrating librations.](https://i.sstatic.net/wRTb2.gif)](https://i.sstatic.net/wRTb2.gif)

You can find all those images and further explanation in the linked wikipedia articles on [tidal locking](https://en.wikipedia.org/wiki/Tidal_locking) and [libration](https://en.wikipedia.org/wiki/Libration).

> **Comments:**
> **username_3**: Read username_1's comment on the question, you are talking about the far side of the Moon **not** the Dark Side  
> **username_2**: Yes, the question and my answer are about the far side. However, this side is typically referred to as [*dark side*](https://en.wikipedia.org/wiki/Far_side_of_the_Moon) even though it does get illuminated by the sun in periods of two weeks. I don't see what else the *dark side* could mean in this context.  
> **username_3**: Erroneously refered to as the dark side, you could try pointing this out  

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