Absolutely. This is why we always see "the face" of the Moon. Many people think that the moon is just sitting still, but if it was we would see the far side of the Moon as it orbited the Earth. The reason why we see only the face of the Moon all the time is actually quite awesome. It's because of Tidal Synchronization (or Synchronous Rotation). The Earth has pulled the Moon in to us with its gravitational pull to synchronize its orbit around Earth with the same exact amount of time it takes for the Moon to rotate. In other words, it takes 27.3 days for the Moon to orbit the Earth and it takes 27.3 days for the Moon to complete a full rotation.
This actually was hard for me to understand at first but this little experiment helped a lot. Take two oranges (or balls, or anything round) and use one as the Earth model and one as the Moon model. Draw an X on the Moon model (this will represent the Face of the Moon). Put the Earth model on a table . Now take the Moon model and move it in a circle, orbit, around Earth model about 1ft away and keep the X always facing the Earth model. Surprise! You'll see that to keep the X facing the Earth model, you have to rotate the Moon model as it goes around the Earth model. Also, you will see the Moon model will have to rotate at the same exact time as it orbits the Earth for us to always see the face. In other words, by the time you get the Moon model to make on full orbit around the Earth model, it will also make one full rotation itself. If the Moon did not rotate, we would eventually see all side of the Moon. Cool huh?
In fact, almost all of every planet's moons actually do this same thing. Hyperion, a moon of Saturn is not tidally synchronized because of the gravitational pull of the other moons around it. It is in a constant struggle for it. Once it starts to get close to being synchronized, another moon's gravitational pull changes it's rotational state. Poor, Hyperion...
Cheers!
K.A. Ball
I'll have to do this. Pretty neat. But my question is (and maybe when I do the experiment, it'll be answered) if the moon is rotating at the same speed as earth, etc, though I could understand why WE (America) only sees the one side, wouldn't China or maybe Australia see the "dark side' constantly? Ive always been curious about this too. And, ironically, was thinking of this very thing just a few weeks back.
ReplyDeleteCheers,
Heather
When you conduct the experiment, draw an A where the U.S. would be on the Earth model and a C where China would be. You'll see that as you orbit the Moon model with the X always facing the Earth model that the U.S. and China would always see the same part of the Moon as it goes by. You will see that the dark side of the Moon will never face any part of Earth.
ReplyDeleteHope this helps!!