The moons lack of rotation.

reply to post by Phage


Bless you Phage.

You are the voice of reason - as always.

reply to post by Soylent Green Is People

To me I got confused right off.
Thanks but I didn't need a top view or other scenarios because
I had already figured out the 'alien' point of view or the Earth Moon System as
viewed from the Sun as this obvious "rotation" comes about as we all know the Sun
eventual sees every side of the Moon.

Thats the 'rotation' evidence quite clear to every one that the Sun see every side
of the Moon. Also quite clear is the same face of the Moon constantly faces
the Earth as evidence there is no rotation of the Moon. To go any more scientific
you come up with the Barycenter or the Moon has no energy to even power a watch.

Unless one expects to go for a spin in space I don't see much to fuss about the
obvious Moon always facing Earth having no rotation just as geocentric satellites
much closer to the Earth which the Sun would see 'rotate' every day.

Originally posted by Phage
reply to post by TeslaandLyne

 

See one of the Google summaries...

You are a bit confused. You are posting about the revolution of the Moon, not its rotation. The Moon revolves about the Earth/Moon barycenter just as the Earth revolves around the Earth/Sun barycenter.

The Moon also rotates about its rotational axis just as the Earth rotates about its rotational axis.

edit on 9/10/2012 by Phage because: (no reason given)

Yeah I know about the center of mass of the earth moon system like years ago.
Its the same thing as the so called 'synchronous rotation' or what ever someone posted and
people keep posting about.

The moons lack of rotation.

in the OP he does not want revolving in a earth moon system.
I told him about the rotation of the Moon so please do likewise.

Originally posted by Sublimecraft
reply to post by Phage

 

Bless you Phage.

You are the voice of reason - as always.

You should help him out with rotation and revolving if at all possible.

reply to post by TeslaandLyne


If you were to view the Moon as the center of the Earth-Moon system (with the Moon stationary in the middle and the Earth orbiting it), could the Earth orbit around the Moon and still have the same side of the Moon facing it if the Moon weren't rotating?

Originally posted by CLPrime
reply to post by TeslaandLyne

 

If you were to view the Moon as the center of the Earth-Moon system (with the Moon stationary in the middle and the Earth orbiting it), could the Earth orbit around the Moon and still have the same side of the Moon facing it if the Moon weren't rotating?

That sounds like only Soylent Green Is People could figure that one out cause the easy
steps he gave me confused me right off. We only need what is real and see no other way
to explain things.

The Moon faces the Earth for all time as we have been told by our parents no less or a truly
informative TV program or 1919 magazine is a good hint there is no rotation. Going more
I was surprised of the lack of energy intrinsic to the moon.

There is no stationary point except the barycenter so there is no other viewing possible.
In any case I can't solve your question.
If others see more clearly I might become enlightened if you check them out.

reply to post by TeslaandLyne


The barycenter seems to be your crutch to avoid the question. But the barycenter of the Earth-Moon system is within the Earth, so it shouldn't even need to enter the picture. For all intents and purposes, the Moon orbits the Earth.

It is perfectly valid to imagine the Earth-Moon system from the perspective of the Moon, with the Earth orbiting around it. Of course, gravitationally, that's not how it's actually happening, but it's legitimate observationally.

So, imagine the Moon sitting stationary at the center. The Earth orbits around it. If the Moon doesn't spin, then as the Earth orbits it views every side of the Moon. The only way to get the same side of the Moon to face the Earth is to have the Moon spin at the same rate as the Earth is orbiting it.

Even though we look at this same situation with the Earth at the center, it is still the same situation. The Moon must be rotating in order for the same side to always be facing us.

As the OP I didnt think I would start such an extensive discussion because of my lack of knowledge - you guys are brilliant.

Originally posted by youwillneverknow
As the OP I didnt think I would start such an extensive discussion because of my lack of knowledge - you guys are brilliant.

Ha ha! There is no such thing as a subject on ATS that is immune to extensive discussion.
We can discuss the crap about any given topic.



Basically, my answers to your original question in a nutshell:

- The Moon DOES rotate once every revolution around the Earth (which admittedly does "hide" that rotation, in a way).

- The Moon does this because it is tidally locked to the earth, which means the same side of the moon is always facing the earth throughout the Moon's orbit.

- This tidal locking is not unique to our Moon. There are over 30 other moons in our solar system that also do this (that are also in tidal lock with its parent planet): The four main Moons of Jupiter -- Io, Europa, Ganymede, and Callisto, plus four others; some of the major moons of Saturn -- Titan, Enceladus, Mimas, Rhea, Iapetus, and several others; both moons of Mars; five moons of Uranus; two moons of Neptune; plus other Moons.

- There are also other planets orbiting other stars that we think are tidally locked to their star, so the time it takes them to revolve around their star is the same amount of time it takes to rotate once.

Originally posted by TeslaandLyne

Originally posted by CLPrime
reply to post by TeslaandLyne

 

If you were to view the Moon as the center of the Earth-Moon system (with the Moon stationary in the middle and the Earth orbiting it), could the Earth orbit around the Moon and still have the same side of the Moon facing it if the Moon weren't rotating?

That sounds like only Soylent Green Is People could figure that one out cause the easy
steps he gave me confused me right off. We only need what is real and see no other way
to explain things.

The Moon faces the Earth for all time as we have been told by our parents no less or a truly
informative TV program or 1919 magazine is a good hint there is no rotation. Going more
I was surprised of the lack of energy intrinsic to the moon.

There is no stationary point except the barycenter so there is no other viewing possible.
In any case I can't solve your question.
If others see more clearly I might become enlightened if you check them out.

edit on 9/10/2012 by TeslaandLyne because: (no reason given)

OK, several people have made it so simple that a 5 year old could understand, yet you still can't comprehend it. The moon DOES rotate on its axis, it also revolves around the Earth. They have given you good hands-on ways to demonstrate this for yourself. If the moon did not rotate on its axis, we wouldn't see the same "face" at all times, we'd see the whole thing.
Practically all moons of planets in this system do the same thing. A few don't, but most do. It's not something that's unusual or weird or done by aliens. If your parents told you the moon doesn't rotate, they were wrong. If you read it in a magazine, the magazine was wrong. This is very elementary level knowledge and you are out of excuses for not understanding it other than you just don't want to.
You can rant and rave and whine and cry, but it's not going to change the fact that the moon does, indeed, rotate on its axis. Those with any form of basic understanding of what a circle is can see this very clearly and it is easy to demonstrate using methods given to you here. If you choose to blindly accept something you WANT to be true, then be prepared for people to roll their eyes at you.
It's better to sit back and let people think you're a fool than to open your mouth (or type it out) and remove all doubt.

I think he is asking why the same side is facing the earth all the time. I think they call that tidal lock or something like that. I've researched the subject about why our moon and some other moons in our solar system are like that and have never really got an answer because I don't think anyone knows. It seems as if there might be something that is more attracted to the earth in the side facing this way than on the other side of the moon. Maybe this side is more dense, maybe certain mineral complexes are on this side, or maybe a lot of different reasons. People often try to explain something with what they know even though it is sometimes irrelevant. I still think it is so the moon can keep an eye on us.

Originally posted by TeslaandLyne
That sounds like only Soylent Green Is People could figure that one out cause the easy
steps he gave me confused me right off. We only need what is real and see no other way
to explain things...

OK -- Below are some visual aids that go along with what I said:

Here is the Earth and Moon. This graphic is looking "down" on the earth and moon from above their north poles. The Moon (red circle) is shown in 12 different locations as it makes its 29-day orbit around the Earth.

The red line indicates the side of the moon that is always facing Earth. As the Moon orbits the Earth, it is oriented so that same face of the Moon is always pointing toward the Earth.





NOW, lets take each of those 12 orientations of the Moon, and put them together -- one by one -- in a little animation, as seen here. Each frame of this animation is one of the 12 orientations of the moon shown, each in order:



This animation repeats itself, so what it shows would be the continuous motion of the moon, month after month, year after year.

Looking at this animation, it certainly appears that the Moon rotates.

Note: Please ignore the slight wobble in my animation -- that was inadvertent. I'm not that skilled at making ".gif" files, and I didn't feel like going back and fixing the "wobble".

reply to post by Soylent Green Is People


That is actually a winding spring motion which comes back upon itself and loops because the orbit is not around the earths equator as we go around the sun. I don't know how to load pictures to show this, and I really don't want to learn how to load pictures either

reply to post by rickymouse

rickymouse --

Tidal locking is well-understood, and has to do with the orbital drag caused by the gravitational pull of a parent body (such as a planet) distorting another orbiting body (such as a moon). Over time -- maybe millions of years -- that orbital drag will cause the smaller orbiting object to slow its rotation -- and more importantly synchronize its rotation -- with the period of its orbit.

Look at this Wikipedia article under "Mechanism":
Tidal Locking

Tidal locking is quite common. There are over 30 moons in our solar system that are tidally locked to their planet, plus there are extrasolar planets that are tidally locked to their star.

reply to post by Soylent Green Is People


The info I read on what you stated and implied that it was a theory but it should have been evident in moons that were older and it wasn't. It also referenced some moons of bigger planets that should be locked by this theory but weren't. So if it isn't consistent is it really the cause? Some scientists said it may not be the right theory but they aren't the ones who got heard. I like to look at many theories to find out what is real, not just the accepted ones. The other scientists didn't have a theory though, they just said this one might be flawed. Doesn't matter to me anyway, if people want to believe in the theory of the time I guess it's ok.

Originally posted by rickymouse
It also referenced some moons of bigger planets that should be locked by this theory but weren't. So if it isn't consistent is it really the cause? ...

If you are talking about the article I linked, there was nothing there about Moons that should be tidally locked but aren't.

There is a section about moons that are "likely" to be tidally locked based on calculations, but there is not enough observational data for us to confirm whether or not they are in fact tidally locked to their planet.

reply to post by Soylent Green Is People


The article I read a while ago was something to do with the possibility of the baricenter being off center possibly because of an asteroid hitting it or something. I can't remember off hand but I think that baricenter is something to do with center of gravity.

Originally posted by Soylent Green Is People

The best illustration, imho. Besides, how can a cosmic body have absolutely no rotation? That is impossible. Everything in the universe has rotation, however slight.

We are all imagining the Moon to be "rolling" around this imaginary, 2 dimensional gravitational well created by the Earth...whilst the Earth does the same around the Sun and so on and so on....
No wonder it doesnt seem to make sense.

Would it make more sense that space is in fact made up of pieces, and that these pieces have actual quantum density (quantum Mass) so we can start to imagine something more plausable ?

Although objects seem to orbit other denser objects in circles due to a 2 d graviity well..this MAY be the result of quantum particles conserving angular momentum through quantum gradients of density ;i.e travelling in straight lines through 3/4/5/6 dimensional space.

Unfortuantely you cant demonstrate quantum density gradients using balls and tangerines so although the theories all match up; until Gravities spooky ability to affect everything instaneously is explained without the use of EQUALLY imaginary faster than light particles like Gravitons; there is no abosolute right or wrong answer on this at the moment.

I do question the moon as some kind of generator