[sullivt8]

Hey all, new user here.

I mainly created an account to offer this idea: Is it possible that the earth's magnetic poles could be evidence that the solid inner core, made mostly of iron, spins in a way as to generate magnetism, causing magnetic pull throughout the whole planet, much the same way a refrigerator magnet magnetizes to most any magnetic substance? I mean, I'm in no way a scientist. But to me it sounds possible that all the magnetism on earth is centered around the idea that (atomically) electrons spin in an orbit, causing magnetism.

So, what if earth's magnetism is due to it's mostly iron mantle/crust spinning orbitally around the iron core? Like an enormous version of an iron atom's electron around a nucleus.

[rktpro]

My book of class 4 might agree with you.

[timo]

I don't know much (read: I know pretty much nothing) about the earth magnetic field. But I thought that's roughly the mainstream view. So how does your idea differ from the ideas that scientists have?

[physics confusion]

sullivt8, on 12 June 2011 - 11:32 PM, said:

Hey all, new user here.

I mainly created an account to offer this idea: Is it possible that the earth's magnetic poles could be evidence that the solid inner core, made mostly of iron, spins in a way as to generate magnetism, causing magnetic pull throughout the whole planet, much the same way a refrigerator magnet magnetizes to most any magnetic substance? I mean, I'm in no way a scientist. But to me it sounds possible that all the magnetism on earth is centered around the idea that (atomically) electrons spin in an orbit, causing magnetism.

So, what if earth's magnetism is due to it's mostly iron mantle/crust spinning orbitally around the iron core? Like an enormous version of an iron atom's electron around a nucleus.

O.K. First off, the core at hte centre of Earth is MOLTEN, not solid. Secondly, the 'magnetic poles' are the point at which the Electromagnetic feild (commonly called the atmosphere) of earth are at their weakest given the axis (in a line with the magnetic poles) of the core rotation.

[timo]

physics confusion, on 13 June 2011 - 11:13 AM, said:

O.K. First off, the core at hte centre of Earth is MOLTEN, not solid.

That's what I also thought. But Wikipedia disagrees with that. From Wikipedia's article about the Earth Core:

Quote

Seismic measurements show that the core is divided into two parts, a solid inner core with a radius of ~1,220 km and a liquid outer core extending beyond it to a radius of ~3,400 km

This post has been edited by timo: 13 June 2011 - 11:23 AM

[Ophiolite]

physics confusion, on 13 June 2011 - 11:13 AM, said:

O.K. First off, the core at hte centre of Earth is MOLTEN, not solid.

No. You are mistaken. The inner core is solid; the outer core, where the magnetic field is generated, is molten. This was recognised because of the inability of seismic shear waves to pass through the outer core.

Edited addition: I've just noticed that you have repeated the error from a previous thread of saying that the magnetic field and the atmosphere are the same thing. They most certainly are not. They are two completely different things: one is a field the other is a mix of gases.

sullivt8, I am not quite sure what you mean by this:

Quote

iron mantle/crust spinning orbitally around the iron core

The mantle and crust are composed of silicates, not iron. They do not 'spin orbitally', whatever that means, around the core, but rotate with it. (There is some recent research that suggests there may be a very small slippage between core and mantle.) The magnetic field is generated by a self exciting dynamo arising from convection currents in the outer core. This is fairly well established as detailed computer models of the system give an excellent match to observations of the field. (As a complete aside it was, I think, Queen Elisabeth's physician, William Gilbert who first recognised that the Earth acted like a giant magnet.)

You are broadly correct that magnetic charge arises from electrons: magnetic fields are generated by the movement of charged entities. Google a few sources to get a more detailed description of how it all works.

This post has been edited by Ophiolite: 13 June 2011 - 12:38 PM

[sullivt8]

Ophiolite, on 13 June 2011 - 12:29 PM, said:

sullivt8, I am not quite sure what you mean by this:
The mantle and crust are composed of silicates, not iron. They do not 'spin orbitally', whatever that means, around the core, but rotate with it.

I'm proposing that the molten layer of earth's core would basically make the solid inner core not spin at all. As a very rough experiment example, floating a piece of ice in a bucket of water, then spinning the bucket would cause the bucket (earth's crust/mantle) to move. The water (molten outer core) would shift a little, but not move much at all. The piece of ice (inner core) would stay roughly in the same position it was before you spun the bucket.

[Leader Bee]

sullivt8, on 15 June 2011 - 12:53 AM, said:

As a very rough experiment example, floating a piece of ice in a bucket of water, then spinning the bucket would cause the bucket (earth's crust/mantle) to move. The water (molten outer core) would shift a little, but not move much at all. The piece of ice (inner core) would stay roughly in the same position it was before you spun the bucket.

Isn't this how they discovered why Jupiters atmosphere appears in bands? Does someone have more info on this?

[Ophiolite]

sullivt8, on 15 June 2011 - 12:53 AM, said:

I'm proposing that the molten layer of earth's core would basically make the solid inner core not spin at all. As a very rough experiment example, floating a piece of ice in a bucket of water, then spinning the bucket would cause the bucket (earth's crust/mantle) to move. The water (molten outer core) would shift a little, but not move much at all. The piece of ice (inner core) would stay roughly in the same position it was before you spun the bucket.

That's a good experiment. However, it seems you have not conducted it. Drag between the different elements of the set up will cause the inner ice to rotate. If you model with the viscosities you actually obtain in the interior of the Earth the drag is proportionally greater.

Moreover you are missing the point that the core is rotating, not because the crust is rotating, but because of the angular momentum inherited from those components that came together to form the Earth and from which the core separated.

Quote

Isn't this how they discovered why Jupiters atmosphere appears in bands? Does someone have more info on this?

I'm not sure what is the this you are referring to. The banding on Jupiter and the other giant planets is a poorly understood phenomena. Certainly it is governed by atmospheric conditions of pressure and temperature that determine which compoounds will condense to form clouds, and by the global circulation patterns. But the details still elude us.

[Leader Bee]

Ophiolite, on 15 June 2011 - 04:17 PM, said:

I'm not sure what is the this you are referring to. The banding on Jupiter and the other giant planets is a poorly understood phenomena. Certainly it is governed by atmospheric conditions of pressure and temperature that determine which compoounds will condense to form clouds, and by the global circulation patterns. But the details still elude us.

I am refering to this experiment:



Though the banding isn't quite as prominent in other cases where I have seen this performed. Perhaps I am missing a certain criteria of the experiment. (something makes me feel this is the rotation of a certain aspect of the experiment but i couldn't say for sure)

[Ophiolite]

Yes, this is a nice demonstration, as the narrator says, of a Hadley cell. That was part of what I was including in my more general comment on global circulation patterns. Wikipedia has an introductory piece on this, with further links. But this is only part of the story about the banding. We have much more to learn.

[truedeity]

physics confusion, on 13 June 2011 - 11:13 AM, said:

O.K. First off, the core at hte centre of Earth is MOLTEN, not solid. Secondly, the 'magnetic poles' are the point at which the Electromagnetic feild (commonly called the atmosphere) of earth are at their weakest given the axis (in a line with the magnetic poles) of the core rotation.

The earths inner core is thought to be solid. The reason is because the melting point of iron is increased with pressure. So the pressure in the outer core would be less than the pressure in the inner core. It might also be interesting to note that the gravity situation at the inner core would be near zero. So it's not so much that the solid core is spinning, its the earth itself rotating around its axis, and because the outer core is liquid so the inner core is constantly being massaged by the outer core, because of the earths rotation on its axis.

truedeity, on 7 October 2011 - 12:46 AM, said:

The earths inner core is thought to be solid. The reason is because the melting point of iron is increased with pressure. So the pressure in the outer core would be less than the pressure in the inner core. It might also be interesting to note that the gravity situation at the inner core would be near zero. So it's not so much that the solid core is spinning, its the earth itself rotating around its axis, and because the outer core is liquid so the inner core is constantly being massaged by the outer core, because of the earths rotation on its axis.

This is why we have a magnetosphere which protects us from solar flares.

I have a suspected that solar flares play some role in pole reversals. Pole Reversals have been a mystery to scientists, it is assumed that pole reversal is a subtle and slow drifting phenomena. I don't believe this. As we have established, the earths core is like a magnet and we all know that if you send an electrical current through a magnet its N/S poles instantly reverse. I believe solar flares somehow cause the earths inner core to get an electrical discharge, but I have not figured out exactly how that occurs. What I can say is that scientist have tracked the history of berillium-10 from ice rods extracted in Greenland. berillium-10 is only found in solar flares and galactic cosmic rays, and higher levels of berillium-10 seem to correlate with ice ages. And Pole reversals are consequently thought to be one of the main triggers of the ice age phenomena. Is it possible that the Sun storms or solar maximums play a major role in pole reversal?

[keep_talking]

The core of the Earth is the reason we have a magnetosphere, and ultimately an atmosphere.

Scientists believe this to be true by comparison of earth to mars. Mars is roughly the same size as earth, has similar mass and yet, has no sustainable atmosphere, and is completely barren. if Mars had a superfluidic molten core of iron like earth, it more than likely would be a green planet of water and plant life. Seeing as this is not the case, the sun's radiation is free to ravage the surface of mars making it the barren wasteland it is today. This is thought to not always be the case. The downfall of Mars is thought to be due to its size. At one time, mars' core was spinning much like Earth's core, allowing the formation of water on the surface. The water was free flowing, until Mars' magnetosphere was stripped away due to the core of Mars had stopped spinning.

The core of the Earth is made mostly of iron, giving off a magnetic charge..and a magnetosphere. As it spins, it ensures the sun is not free to assault the surface with radiation. This allows for an atmosphere to form around earth, allowing for a water cycle..and ultimately organic life.

Thanks Earth!

[Ophiolite]

While agreeing with most of what you wrote I must take exception to this:

keep_talking, on 9 January 2012 - 09:37 AM, said:

Mars is roughly the same size as earth, has similar mass ...

Mars is an order of magnitude smaller than the Earth. It is half the radius of the Earth, but only a tenth of its mass. It is this smaller size that is responsible for the barren condition of the planet today. Small size means rapid cooling, means no sustained magnetic field and so atmospheric erosion.

[keep_talking]

Ophiolite, on 9 January 2012 - 09:50 AM, said:

While agreeing with most of what you wrote I must take exception to this:

Mars is an order of magnitude smaller than the Earth. It is half the radius of the Earth, but only a tenth of its mass. It is this smaller size that is responsible for the barren condition of the planet today. Small size means rapid cooling, means no sustained magnetic field and so atmospheric erosion.

Its not the size that is causing the rapid cooling of the surface of mars, its the core of mars (thought to be completely solid) that does not flow like Earth's core. The flowing of the core is what produces the magnetosphere. The magnetosphere is responsible for the condition of the water on the surface of Earth to remain.

I cannot remember the term used, but theres something that says the Sun's radiation can and will degrade the properties of water. There is no atmosphere to protect the surface from solar winds, and no magnetosphere to protect the surface (that would be covered in water) from direct radiation from our sun.

At one time, Mars had flowing water on its surface. At this time, the core of Mars was active. When the core kicked the bucket, Mars lost it's magnetosphere, and ultimately its atmosphere.

[Ophiolite]

Please reread what I wrote. Or, better yet I'll lay it out for you step by step.

Mars is only 10% the mass of the Earth.
The Earth has retained sufficient heat from formation and from the decay of radioactive elements in the mantle, so that its core remains partially molten.
This molten core is responsible for the Earth's magnetosphere which helps to protect the atmosphere from erosion by the solar wind.
Mars, because it is much smaller has not retained its heat and that is why it has no partially molten core and no magnetosphere.

I hope this is clearer now. It is the size of Mars that has led to the loss of atmosphere.

[keep_talking]

keep_talking, on 9 January 2012 - 09:37 AM, said:

The core of the Earth is the reason we have a magnetosphere, and ultimately an atmosphere.

Scientists believe this to be true by comparison of earth to mars. Mars is roughly the same size as earth, has similar mass and yet, has no sustainable atmosphere, and is completely barren. if Mars had a superfluidic molten core of iron like earth, it more than likely would be a green planet of water and plant life. Seeing as this is not the case, the sun's radiation is free to ravage the surface of mars making it the barren wasteland it is today. This is thought to not always be the case. The downfall of Mars is thought to be due to its size. At one time, mars' core was spinning much like Earth's core, allowing the formation of water on the surface. The water was free flowing, until Mars' magnetosphere was stripped away due to the core of Mars had stopped spinning.

The core of the Earth is made mostly of iron, giving off a magnetic charge..and a magnetosphere. As it spins, it ensures the sun is not free to assault the surface with radiation. This allows for an atmosphere to form around earth, allowing for a water cycle..and ultimately organic life.

Thanks Earth!

Ophiolite, on 9 January 2012 - 10:59 AM, said:

Please reread what I wrote. Or, better yet I'll lay it out for you step by step.

Mars is only 10% the mass of the Earth.
The Earth has retained sufficient heat from formation and from the decay of radioactive elements in the mantle, so that its core remains partially molten.
This molten core is responsible for the Earth's magnetosphere which helps to protect the atmosphere from erosion by the solar wind.
Mars, because it is much smaller has not retained its heat and that is why it has no partially molten core and no magnetosphere.

I hope this is clearer now. It is the size of Mars that has led to the loss of atmosphere.

I bolded my quote of Mars' size being its problem. Would there be a direct correlation between size, mass, and heat loss?

How can mars be half the size of Earth, but only be 10% of its mass?

[swansont]

keep_talking, on 9 January 2012 - 10:34 AM, said:

Its not the size that is causing the rapid cooling of the surface of mars

An object such as a planet loses energy via radiation, the rate of which depends on the surface area. But the energy content depends on the volume. All else being equal, a smaller body will radiate a larger fraction of its energy away per unit time, so it will indeed cool faster because of its size.

keep_talking, on 9 January 2012 - 11:14 AM, said:

How can mars be half the size of Earth, but only be 10% of its mass?

Half the radius is 1/8 of the volume (0.125), and the mass ratio is 0.107. You'd only need a small difference in composition to account for this.

[Sorcerer]

sullivt8, on 12 June 2011 - 11:32 PM, said:

Hey all, new user here.

I mainly created an account to offer this idea: Is it possible that the earth's magnetic poles could be evidence that the solid inner core, made mostly of iron, spins in a way as to generate magnetism, causing magnetic pull throughout the whole planet, much the same way a refrigerator magnet magnetizes to most any magnetic substance? I mean, I'm in no way a scientist. But to me it sounds possible that all the magnetism on earth is centered around the idea that (atomically) electrons spin in an orbit, causing magnetism.

So, what if earth's magnetism is due to it's mostly iron mantle/crust spinning orbitally around the iron core? Like an enormous version of an iron atom's electron around a nucleus.

To summarise : yes the earths core creates a magnetic field that surrounds the earth.

"Is it possible that the earth's magnetic poles could be evidence that the solid inner core, made mostly of iron, spins in a way as to generate magnetism, causing magnetic pull throughout the whole planet, much the same way a refrigerator magnet magnetizes to most any magnetic substance?"

From what is known/assumed by weight of evidence it is a core mainly composed of some nickel and mostly iron, it acts as a dynamo, and yes it spins.

"So, what if earth's magnetism is due to it's mostly iron mantle/crust spinning orbitally around the iron core?

Yes, but seems to be a rhetorical question, not seeking any extra information.

"Like an enormous version of an iron atom's electron around a nucleus."

Hmmmmmm, I suggest trying to understand a dynamo and quantum theory first, then coming back to your analogy.

This post has been edited by Sorcerer: 9 January 2012 - 11:43 AM

[keep_talking]

A planet cannot have a molten outer core without the surface having constantly changing plate tectonics.

Earth is one of the FEW planets we know of that has a constantly changing tectonic plate.

Unfortunately, the probes we sent into space to look at mars are not equipped with the proper equipment to measure if Mars still has "Marsquakes" and there is no sufficient data to prove or disprove this.

Can we say the rapid cooling of the surface of Mars had nothing at all to do with its distance from the sun? I want to say there are a multitude of factors in Mars' wasteland like surface.

Fascinating conversation to say the least.