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MDT
Something that has puzzled me is how did the earth's iron core become so magnetic? If you look at surface iron and iron ores, only a small percentage is naturally magnetic, even though all the surface iron has been bathing in earth's magnetic field during crystalization. At the same time, if one heats natural magnets, once they melt the crystal/atomic alignment gets random and the natural magnetism declines of goes away completely. That is why super magnets work better in extreme cold instead of high heat.

Once a magnetic iron core in the earth is set up, by whatever means, it might be self perpetuating, inspite of the 8000c core temperature increasing the degree of atomic movement in the cystal magnetic alignment. But what was the original magnetic field that helped induced the current magnetic iron core, so the earth's core didn't end up with only a small percentage magnetism, in proportion to what is on the surface?
MDT
I like picking on the earth's iron core and magnetic field because it is one of those dogmas of science, very similar to those in religion, i.e., strongly help while unprovable. One sort of gets the same reaction from science as one gets from religion, if you dare question the unprovable that is accepted as truth.

If you look at the history of this dogma it is at least 200 years old and could have been deduced in Faraday's time. First of all, lodestone has been known to have magnetic properties for thousands of years. By the iron age it was probably known to contain iron. Little pieces of lodestone had been used to help navigate ships and was the basis of the first compasses for centuries before Faraday.

When Faraday experimented with magnetic field and saw how they were aligned around a magnetic, the logical speculation was that maybe the earth was a big magnetic made of lodestone. The lodestone we find on the surface came from the bowels of the earth, maybe from its magnetic center. From that the iron core magnetic theory was born, but still sort of censored by religion. This was was the abode of hell. But in sciences defense, war is hell, and Mars the god of war is equated with the metal iron. It hasn't really been questioned since then. It has been refined with nickel to keep it in vogue with the better nickel magnets we can make in the lab. But also to add some extra kick to address insulation considerations.

The dogma is so well protected that once flaws are found and can't be just ignored, alternate explanations appear to help protect it from harm. A simple earth formation from a cloud of dust has the problem of iron oxidation like all the minerals in the crust. So we cheat oxidation with asteroids. But are asteroids pure magnets? And would serious collisions with the earth, heating these magnets, sort of mess up their magnetic properties?

Don't get me wrong, the iron core might be true. All I am saying it is not provable, yet is treated like it is a fact of life. This is religious dogma. Just because there is no God involved doesn't exempt the nature of faith in an unprovable. Maybe this theory hangs on until something better appears. But dogma censors all exceptions, so nothing is allowed to change. It is stuck in that transition between religion and science.
Pan
The Earth's magnetic field isn't thought to be the effect of magnetized iron, but because of the spinning liquid metal, aka the "dynamo effect."
kaneda
MDT. Earth has a solid (mainly) iron core inside liquid (mainly) iron outer core. As Earth rotates they move at different rates which generates the magnetic field and causes it to wander and eventually to flip over. The dynamo effect as Pan calls it.
Saltpeter
There are no dogmas in science, except Nullius in Verba.
Montec
Hello all

Another theory is the rotation of the Earth with a net charge will generate a magnetic field. Whether the charge is positive or negative will determine the polarity of the magnetic field. Zero net charge would mean no magnetic field. Of course there may be some residual magnetic field from the iron core but the temperature at the core is above the Cure temperature for iron.
Space is full of charges either from the Sun or from the local gas cloud. The Sun also flips its magnetic field to so I am wondering if the Sun cycles through bouts of emitting predominantly electrons or protons on the solar ecliptic.

smile.gif

kaneda
Saltpeter. Science is full of dogmas where speculations are accepted as truths.
kaneda
Montec. The sun flips it's magnetic field every 11 years like clockwork, which coincides with a solar maximum. As the sun works by fusing hydrogen into helium and emits the by products of that reaction, I would think that what it emits hardly ever changes while it is on a set cycle.

Space at Earth's distance contains maybe ten atoms of hydrogen per cubic cm and other odd particles. I doubt that the charges of this insignificant amount would count.
cjameshuff
QUOTE (Montec+Mar 15 2007, 12:24 AM)
Another theory is the rotation of the Earth with a net charge will generate a magnetic field. Whether the charge is positive or negative will determine the polarity of the magnetic field. Zero net charge would mean no magnetic field. Of course there may be some residual magnetic field from the iron core but the temperature at the core is above the Cure temperature for iron.


The Earth is certainly charged, and its rotation would certainly produce an overall magnetic field because of that charge, unless the charged particles for some reason stay stationary as the planet rotates. However, I'd think that field would be far weaker than the dynamo-generated field caused by the convection currents in the core, weaker even than the field induced by the sun's magnetic field. The Earth isn't that strongly charged, and it's not rotating that fast.

Also, I'd expect the charges being lost/gained from either Earth or the sun to quickly settle into an equilibrium, and for the final balance to be determined by the relative masses of electrons vs. protons/heavier nuclei and ions (and in the case of the sun, the energies given to each by the fusion process)...it probably varies somewhat with the amount solar activity, but I'd be very surprised if it ever switched signs. Then there's the tilt with respect to the rotation axis, and all the irregularities in the field...it's pretty clearly generated by the core dynamo.
Montec
Hello kanada, et al.

Here is an image from NASA/Ulysses
User posted image
click to enlarge

Notice that the proton density (positive ions) is higher in the ecliptic band. There are also some spikes in this area but it is not clear if these spikes are long term phenomenon. If these spikes are more or less long term then the Earth's ecliptic path (which has a 100,000 year period) will encounter different mixes of charged particle densities.

smile.gif

Saltpeter
QUOTE (kaneda+Mar 15 2007, 01:32 PM)
Saltpeter. Science is full of dogmas where speculations are accepted as truths.


Humbled, I bow to your authority.

Eppur si muove.
kaneda
saltpeter. Galileo might have asked where the proof was if confronted with the big bang, what goes on inside a black hole, superstrings, etc.

So called puzzles of QM like the double slit experiment and quantum entanglement are just parlour tricks as I have shown elsewhere.

PS. Isn't potassium nitrate spelt saltpetre?
kaneda
Montec. An x-ray view of the sun. By using a device which would normally only detect x-rays and higher energy radiation/particles, we only see the most energetic parts of the sun without the unwanted low energy stuff that we can see with our eyes.

The cooler parts (black) are 5-6,000.C . The hotter parts are notably the sun spots which are magnetic holes in the sun's surface which show the hotter inside of the sun.
johnatphysorg
How does curie temperature for iron vary with pressure??? Is it possible that under extreme pressure the curie temperature is higher than the temperature of the core. In which case the core could be magnetic. I presume that with increased pressure the atoms would be pressed together more firmly and this might be enough to overcome the thermal agitation.

Is someone able to calculate pressure at earth centre based on average density and gradually decreasing gravity. Acceleration due to gravity at centre will be zero. For first approximation I picture a column of water 4000 miles high surely that would produce a very high pressure???
paul h
QUOTE (kaneda+Mar 13 2007, 03:03 PM)
MDT. Earth has a solid (mainly) iron core inside liquid (mainly) iron outer core. As Earth rotates they move at different rates which generates the magnetic field and causes it to wander and eventually to flip over. The dynamo effect as Pan calls it.

Pan, Kaneda,

dynamo effect?
Then what about mars? It has an iron core, ( yes I know,, liquid not solid)it spins and yet all most no magnetic field. Has it just not cooled enough yet or did it have one and has lost it?

http://www.sciencedaily.com/releases/2003/...30307071457.htm
Corvidae
QUOTE (paul h+Dec 10 2007, 11:21 PM)
Pan, Kaneda,

dynamo effect?
Then what about mars? It has an iron core, ( yes I know,, liquid not solid)it spins and yet all most no magnetic field. Has it just not cooled enough yet or did it have one and has lost it?

http://www.sciencedaily.com/releases/2003/...30307071457.htm

There is evidence to suggest mars used to have a magnetic field up to 3.5 billion years ago, then it lost it. The field still exists, but it's VERY weak (May be caused by ionosphere and not the core). There are large differences between the Earth and Mars due to size and composition. Mars is much less dense than Earth or Venus, the density differences along with other data leads some to think it also has a higher sulphur content in the core. Why sulphur? No idea.

The question that begs from looking at Mars and our own planet is what alloys would solidify at the pressures at our core despite the high temperatures. Iron is undoubtedly involved, nickel is highly probable as well. That I know of, we can't duplicate the environment in the core. And they are still making discoveries concerning high pressure molecules. Some crystal formations simply can't be recreated without the combination of heat and pressure at that depth. In the light of recent news about super solids, I'd say there's a very good chance we have no idea what the core is really like.

At this point we really don't know much about Mars core either, other than it is still liquid, rather large for the planet size and not very dense compared to Earth.
K. Margiani
Magnetic Field of The Earth
On the liquid stage of Earth development liquid nucleus was formed from its liquid heavy metal layers in the physical center. Let’s mark this volume with letter n. The rest of the volume of the Earth was the admixture of oxides and other chemical elements fiery liquid masses. Let’s mark this volume relatively with letter m. Geoevolution of Planets at the liquid stage is characterized by the following common regularity. The rotation of liquid layers of m volume toward poles decreases little by little. The inner nucleus rotation in that stage always less then rotational speed of equatorial layer of m masses. On the liquid stage of the evolution convection streams into layers of the m masses are characterized complex turbulent movement around n nucleus. These streams with turbulent movement are moving around the inner nucleus with the direction of the planet’s rotation. At this stage almost convection streams formed summery magnetic field. By this magnetic field was created later stabile magnetic field of the solid heavy metals nucleus. On the liquid stage of evolution magnetic poles of Earth m and n masses exactly coincided with the rotation axis geographical poles. Inner nucleus is in the physical centre

Nucleus n is characterized by the less speed of the rotation then m masses. Because of radioactive demolition super heavy nucleuses into inner nucleus, huge amount of heat is of course released. It helps movement of convection streams om masses during this stage. Because of difference in densities, n and m masses do not mix up with each other. As a result of chemical processes, in m volumes liquid small masses of liquid metal are sediment into n volume. Liquid nucleus step by step gains more amount and volume as well.

Formation almost stable magnetic field, which exists in the inner metal nucleus, began after its hardening process. The influences of metals with paramagnetic qualities are in nucleus on this stage. They has own summary magnetic field and are very insignificant. It is caused by small percentage of those metals. Magnetic field of metal layers with diamagnetic qualities slightly weakens the summary magnetic field ferromagnetic metals layers. It can be said that during liquid stage the Earth had mainly n and m masses summary magnetic field.

During the geoevolution of planets on the first stage its inner nucleus metals layers begin to turn into solid condition. On the second stage D layer of planets becomes solid. It divides convection streams of m masses into ­­­two parts. This causes decreasing of the magnetic field of m masses in the convection streams. Increasing of D layer causes the enlargement of liquid layers density. By this process was decreased convection streams movement and of course came to the end magnetic field made by these streams. On the third stage planets surface begins to turn into solid condition, with formation very thing solid crust.

Into liquid heavy metals nucleus stable dipolar magnetic field is creating during hardening stage of nucleus, only in the case, if nucleus ferromagnetic layers can record the initial magnetic field made by m masses. This is possible when temperature of solid ferromagnetic metals layers are lower, then the Curie point (under conditions of high density and colossal pressure). Parallel with the process of magnetic field weakening caused by m masses, into heavy metals solid nucleus of paramagnetic and diamagnetic metals layers magnetic field undergoes mainly influence of recorded magnetic field by the ferromagnetic metals layers.

At last Earth’s magnetic evolution was transferred to the stage of heavy metals solid nucleus almost stable dipolar magnetic field. From this stage Earth’s dipolar magnetic field is made up almost by the solid metals nucleus ferromagnetic layers. Diamagnetic metals layers into inner nucleus slightly weaken the summary magnetic field of ferromagnetic metals layers.

According to cosmogeological theory if a planet has a vivid rotation around its axis, it should have its own dipolar magnetic field. Only Mercury is an exception. Its rotation was almost prevented by the impact of big asteroid(chunk of huge geolayer). Today's rotation speed would never form dipolar magnetic field of Mercury. Influence of changeable Sun magnetic field on the Mercury’s magnetic evolution is another topic of research.
gnik_isrever
In the core of Earth Shan was placed by Creator God Aton a brilliant crystal, when he created Earth Shan. Our planet was to be the "seed planet" for the entire Nebadon Universe. From the energy of this crystal all of the Nebadon Universe was created. Because this is so, Earth Shan is the oldest planet in our universe, and because it was the first planet it was also designated as the "supply planet" for this sector of the Nebadon Universe.

There is a civilization of people living in the center of the Earth. The civilization is known as ‘Agartha’. This might be hard to believe, I know it was difficult for me at first. However, I now have absolute knowledge of the truth of it.

In January 1956, Admiral Byrd led an expedition to the South Pole. On that expedition he and his crew penetrated two thousand three hundred miles into the center of the Earth. Admiral Byrd states that the North and South Poles are only two of the many openings into the center of the Earth. Admiral Byrd also states that the inner Earth has it’s own sun. Byrd’s theory is that the poles of the Earth are concave, rather than convex, and ships and planes can actually sail or fly right in.

I can’t help thinking about Jules Verne’s famous science ‘fiction’ book, ‘Journey To The Center Of The Earth’ [Joshua Stone, 1995]. The American press announced Admiral Byrd’s discovery, but it was immediately suppressed by our good friends, the secret government. Ray palmer, the editor of the magazine ‘Flying Saucer’, published a detailed [21] story about Admiral Byrd’s discoveries. The United States government bought, stole, or destroyed almost every copy and then destroyed the plates at the printing office. I have been told exactly the same thing happened to an article about Admiral Byrd’s discovery published by ‘National Geographic’. The magazine was released, and the U.S. government gobbled up almost every issue. If the story was not true, why would the government be so nervous?

It is interesting to note that the United States government does not allow planes to fly over the poles. All flights are directed to go around the poles, and any airline pilot flying in those areas will confirm this. Another interesting point is that icebergs are composed of fresh water, not salt water. It is also curious that it is warmer nearer the poles than it is six hundred to one thousand miles away from them. The opening at the poles might also explain why there are so many UFO sightings in those areas. In his book ‘The Hollow Earth’, Dr. Raymond Bernard tells of a man who has conformed Admiral Byrd’s story.

There are over one hundred subterranean colonies underneath the Earth, all but one of them quite close to the surface. These underground cities have been referred to as the ‘Agartha Network’. Their customs vary, but they follow a common, spiritually oriented structure of living - the Melchizedek teachings. The average population of these cities is five hundred thousand, but Telos, beneath Mt. Shasta, has over 1.5 million inhabitants. A second colony of approximately the same size is located beneath the Matto Grosso Plains of Brazil. This Atlantean outpost is called Posid. Although Atlantis and Lemuria have become myth to most people on the surface of the Earth, in reality they are just continuing their evolution underground.

The Melchizedek are an ancient priesthood that disseminates the teachings of the ‘Great White Brotherhood’ throughout the universe.
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