The moon is about one fourth the size of the earth. Like earth it is also pull down all objects towards itself. This is called gravity. However, the gravity on the moon is only about one sixth of that on the earth. It means that if you can jump 1 meter on earth than, you can jump 6 meters on the moon. The moon revolves around the earth. It is a natural satellite of the earth. A satellite is an object that revolves around a planet. The moon takes the about one month to revolve around the earth. As the moon revolves, it also rotates slowly. It takes the moon about one month to rotate. Since it revolves and rotates at the same speed, the same side of the moon always faces us.
The moon shines as brightest object in the night sky. But it does not give out its own light. It only reflects the light of the sun to us. Therefore, depending on the position of the sun, different areas of it reflect light to us on different days, that are why moon appears to change its shape every day. The different shapes of the moon, as visible to us on the earth are called its phases.
Since man first appeared on earth, the moon has been a mystery to him. In ancient times it was even worshiped as a goddess who ruled the night. Right now, we are living in the days when more is being found out about the moon then ever before in the whole history off mankind pictures of the other side of the moon have already been taken by the Americans and the Russians.
The fact that we cannot see the other side of the moon from the earth is due to a simple fact. The moon is a satellite of the earth, a small body that revolves about it, just as the earth moves in an orbit about the sun.
This journey of the moon around the earth takes a certain definite period, about 29 days. The moon also rotates on its axis, but the time it takes for the moon to rotate is the same length of time it takes for it to go around the earth. So we see only one side of the moon.
If you want lo get a picture of how this works, try this: hold your left hand in front of you and clench your fist. Imagine that is the earth. Now take an apple or orange and mark around it with a pencil to indicate two halves. Imagine that is the moon.
Now face one side of the "moon" towards the "earth". Keeping that same side facing the earth, make a complete circle around the earth. You will see that not only did the moon go around the earth, but it also made a complete rotation on its axis. And yet only one side ever faced the earth!
Because the that is the side where the sun's light reflects off the moon. That is why.
The reason is basically the Moon IS rotating , however the rotation is is be off set by it's orbit!
So your always looking at the same side!
Their is a very similar thing happening on the planet Mercury, but the rotation of the planet exceeds the orbit a very small amount.
The many answers to why makes the Quantum Theory seem like a first grade question!
We have what is called a synchronous orbit with the moon, meaning we are tidally locked with it. It takes the moon the same amount of time to revolve once on it's axis as it does for it to orbit the Earth, which is 27 days 7 hours and 43 minutes. Therefore we can only ever see just one side of it from the Earth.
That side of the moon is just slightly heavier than the other, so Earth's gravity pulls that side to face us.
Because the moon rotates on its own axis in almost the exact same time as it completes an orbit of the Earth, so it always presents the same face to us.