Does the Moon Rotate?
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Re: Does the Moon Rotate?
"Does the moon rotate?"
Yes, but it rotates around the center of the Earth.
The Earth, on the other hand, rotates around the center of the Earth, not the moon, for instance.
The peculiar thing about the moon is that it does not rotate around the center of itself.
Yes, but it rotates around the center of the Earth.
The Earth, on the other hand, rotates around the center of the Earth, not the moon, for instance.
The peculiar thing about the moon is that it does not rotate around the center of itself.
- webolife
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Re: Does the Moon Rotate?
This was covered in much discussion earlier in the thread. The moon certainly does ROTATE around it's own polar axis. That rotation is tidally synchronized with it's REVOLUTION about the earth so that it's "face" is always roughly pointing in our direction with a bit of a libration from the perspective of an Earth observer. However, both the centers of the earth and moon do in fact also revolve about the barycenter of the Earth-Moon system [oft referred to as a double planet], not the center of the earth, which is a major factor in the reason we have high tidal bulges both facing and away from the position of the moon wtr the earth, and therefore two high and two low tides daily.lw1990 wrote:The peculiar thing about the moon is that it does not rotate around the center of itself.
Truth extends beyond the border of self-limiting science. Free discourse among opposing viewpoints draws the open-minded away from the darkness of inevitable bias and nearer to the light of universal reality.
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Re: Does the Moon Rotate?
If rotation is synchronized with another body's center point, then it is rotating around that body, not itself.
As you say, one revolution around the Earth is how often the moon spins - the important part is that it's one Revolution around the Earth, not an independent rotation about its own axis. The Earth is acting like the moons axis for rotational purposes. This is not 'synchronized rotation' as science named it, it's just rotation about the Earth's axis. It is theoretically possible the moon could be rotating independently on its own axis at about the same speed as it revolves around the Earth. It is essentially a theoretical impossibility that it could be matching this exactly for hundreds of years or more. Eventually you would just see a slight discrepancy if nothing else, if it was truly independent rotational motion; it's not. If the moon speeds up its revolution around the Earth, its 'spin' will also speed up to face the Earth, if the moon slows down its revolution around the Earth, its spin will also slow down so that it faces the Earth on one side only. This is because its rotational speed is dependent on Earth's location, not its polar axis location.
The moons speed around the Earth is gradually changing (by a small amount) as is its speed of spin. It is a mathematical impossibility that it can do both of these things dependent on its own polar axis and still remain face-locked with the Earth.
For example, if I am sidestepping around you, keeping my torso and face towards you at all times, I'm rotating around you - not my center of mass, basically, I'm not spinning based on my independent location, I'm spinning based on your location.
That is what the moon is doing.
If the moon was rotating around some point between the Earth and Moon, it would rotate faster and break its face-lock with the Earth at some point; it does not do this.
For example, If I was sidestepping around you, about a center point between you and me, I would eventually show you my back side. Merely adjusting what direction I'm facing to match you at all times is not rotating on my axis, it's rotating on your axis. We do not get to say that this is 'rotating on my axis at a very slow speed', because the speed is determined by your location, not my location.
As you say, one revolution around the Earth is how often the moon spins - the important part is that it's one Revolution around the Earth, not an independent rotation about its own axis. The Earth is acting like the moons axis for rotational purposes. This is not 'synchronized rotation' as science named it, it's just rotation about the Earth's axis. It is theoretically possible the moon could be rotating independently on its own axis at about the same speed as it revolves around the Earth. It is essentially a theoretical impossibility that it could be matching this exactly for hundreds of years or more. Eventually you would just see a slight discrepancy if nothing else, if it was truly independent rotational motion; it's not. If the moon speeds up its revolution around the Earth, its 'spin' will also speed up to face the Earth, if the moon slows down its revolution around the Earth, its spin will also slow down so that it faces the Earth on one side only. This is because its rotational speed is dependent on Earth's location, not its polar axis location.
The moons speed around the Earth is gradually changing (by a small amount) as is its speed of spin. It is a mathematical impossibility that it can do both of these things dependent on its own polar axis and still remain face-locked with the Earth.
For example, if I am sidestepping around you, keeping my torso and face towards you at all times, I'm rotating around you - not my center of mass, basically, I'm not spinning based on my independent location, I'm spinning based on your location.
That is what the moon is doing.
If the moon was rotating around some point between the Earth and Moon, it would rotate faster and break its face-lock with the Earth at some point; it does not do this.
For example, If I was sidestepping around you, about a center point between you and me, I would eventually show you my back side. Merely adjusting what direction I'm facing to match you at all times is not rotating on my axis, it's rotating on your axis. We do not get to say that this is 'rotating on my axis at a very slow speed', because the speed is determined by your location, not my location.
- Melusine
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Re: Does the Moon Rotate?
I can't believe I just went through this whole thread. It reads like a thriller with lots of cliffhangers. Even though I got a bit worried when people started to glue race horses to lazy Suzans, overall my faith in the goodness of human nature was strengthened in the end
Anyway, my small contribution will be this very short video illustrating the rotation of the moon as it revolves around the earth (already offered at the beginning of the thread) and this other short video visualizing the earth and the moon orbiting their common center of mass.
Anyway, my small contribution will be this very short video illustrating the rotation of the moon as it revolves around the earth (already offered at the beginning of the thread) and this other short video visualizing the earth and the moon orbiting their common center of mass.
- The Great Dog
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Re: Does the Moon Rotate?
If one person stands against a tree and another person walks around the tree while the first person moves to keep facing the second person, their "faces" are always toward each other. However, the second person revolves around the first person.
There are no other dogs but The Great Dog
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Re: Does the Moon Rotate?
~
All the while, the second person is spinning (rotating) on his own core axis, if he remains facing the tree,
like the moon does.
All the while, the second person is spinning (rotating) on his own core axis, if he remains facing the tree,
like the moon does.
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Re: Does the Moon Rotate?
Wrong. They are both revolving around the (stationary) tree. The tree is the common axis, whether the two people face each other is irrelevant (to the analogy). If both people moved around the tree in synch while rotating on their own axes ....The Great Dog wrote:If one person stands against a tree and another person walks around the tree while the first person moves to keep facing the second person, their "faces" are always toward each other. However, the second person revolves around the first person.
If I have the least bit of knowledge
I will follow the great Way alone
and fear nothing but being sidetracked.
The great Way is simple
but people delight in complexity.
Tao Te Ching, 53.
I will follow the great Way alone
and fear nothing but being sidetracked.
The great Way is simple
but people delight in complexity.
Tao Te Ching, 53.
- The Great Dog
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Re: Does the Moon Rotate?
The circle described by the person with his back against the tree is enclosed by the circle of the one walking around him, therefore, regardless of the tree, the second circle is an orbit around the first circle.
There are no other dogs but The Great Dog
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Re: Does the Moon Rotate?
The point described by the tree is enclosed by the circle of the one walking around it, regardless of the other person, the second circle is an orbit around the tree.The Great Dog wrote:The circle described by the person with his back against the tree is enclosed by the circle of the one walking around him, therefore, regardless of the tree, the second circle is an orbit around the first circle.
If I have the least bit of knowledge
I will follow the great Way alone
and fear nothing but being sidetracked.
The great Way is simple
but people delight in complexity.
Tao Te Ching, 53.
I will follow the great Way alone
and fear nothing but being sidetracked.
The great Way is simple
but people delight in complexity.
Tao Te Ching, 53.
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Re: Does the Moon Rotate?
What's an OP?webolife wrote:Not quite, as the lunar orbit is not coplanar with the ecliptic, and the ecliptic is not coplanar with the galactic disk. Helical is a better description. But if you read my earlier posts you will see that I describe these various relative motions in much the same way as this past post of yours... so have you shifted your current position wrt the OP?
Modern astronomy contends that Earth is moving, orbiting the sun in a curved path. That means the moon is traveling in a “helical” motion faster than Earth's orbital velocity: ~67,000 mph plus its helical velocity. Rather than saying accelerating and decelerating, I should have said that the moon is continually traveling in a helical motion forward and backward in relation to Earth as observed from the sun. The complex centrifugal, centripetal, and Euler forces necessary for a nearly circular orbit are vastly magnified and complicated when applied to helical motion. To complicate matters further, Earth and sun are also traveling in a helical motion rather than in a circle.
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Re: Does the Moon Rotate?
Original Post or Poster.What's an OP?
If I have the least bit of knowledge
I will follow the great Way alone
and fear nothing but being sidetracked.
The great Way is simple
but people delight in complexity.
Tao Te Ching, 53.
I will follow the great Way alone
and fear nothing but being sidetracked.
The great Way is simple
but people delight in complexity.
Tao Te Ching, 53.
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- Joined: Thu Jun 21, 2012 12:36 am
Re: Does the Moon Rotate?
jtb wrote:so have you shifted your current position wrt the OP?
I have shifted my position from the moon accelerating and decelerating to moving forward and backward in relation to Earth as observed from the sun.Grey Cloud wrote: What's an OP? Original Post or Poster.
- webolife
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Re: Does the Moon Rotate?
So with all of that acknowledged complex of relative motions, you still contend that the moon does not rotate?
Truth extends beyond the border of self-limiting science. Free discourse among opposing viewpoints draws the open-minded away from the darkness of inevitable bias and nearer to the light of universal reality.
- webolife
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Re: Does the Moon Rotate?
Melusine,
Thanks for those nice videos which do show clearly the relative motions, including rotations and revolutions of Earth and Moon.
Thanks for those nice videos which do show clearly the relative motions, including rotations and revolutions of Earth and Moon.
Truth extends beyond the border of self-limiting science. Free discourse among opposing viewpoints draws the open-minded away from the darkness of inevitable bias and nearer to the light of universal reality.
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- Joined: Thu Jun 21, 2012 12:36 am
Re: Does the Moon Rotate?
If the same side of the moon continually faces, and is attached to Earth by a string (pull of gravity), no, the moon is not rotating; however, it is orbiting. If the moon's orbit is caused by some external force or push, yes, it is rotating if the same side continually faces Earth. You can't have it both ways. The moon can't be attached by the pull of gravity, one side continually facing Earth, and be rotating.webolife wrote:So with all of that acknowledged complex of relative motions, you still contend that the moon does not rotate?
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