OT: Earth's orbit changing?

[Cipher7071]

What Oleg just said is about the way I understand it. Before a flip the Earth's magnetic field will become more 'patchy.' There will be multiple poles, and plenty of aurorae.

The Earth is a dynamo whose magnetic material is largely liquid. The changes are all supposed to be a result of change in internal flow. Once that evens out, so does the magnetic field. On a geological timescale, it will happen very quickly. As far as we're concerned, it will Last longer, but still not terribly long.

Stock up on sunscreen.

[Kamog]

I never understood this idea of the earth's magnetic poles moving around. How can the magnetic field, which was stable for a long period of time, suddenly reverse polarity? If the magnetic field is produced by the flow of molten material inside the earth, then it takes a tremendous amount of energy to change the direction of flow for so much mass. Where does this energy come from? Also, I thought that a flow of material will not produce a magnetic field unless there's an electrical current flowing through it. I mean, if you take a piece of iron and move it around where there's no magnetic field, it's not going to produce its own magnetic field, would it?

[narf poit chez BOOM]

Why would God make such a beautiful planet and fill it with living things just to burn it to a cinder?

well, suppose the whole world reverted to human sacrifice? and then went worse. in that case, i think we should fry.

I mean, if you take a piece of iron and move it around where there's no magnetic field, it's not going to produce its own magnetic field, would it?

every atom has it's own magnetic field. i don't know why you can only make a magnet out of ferrous material.

[Phoenix-D]

Originally posted by Kamog:
I never understood this idea of the earth's magnetic poles moving around. How can the magnetic field, which was stable for a long period of time, suddenly reverse polarity? If the magnetic field is produced by the flow of molten material inside the earth, then it takes a tremendous amount of energy to change the direction of flow for so much mass. Where does this energy come from? Also, I thought that a flow of material will not produce a magnetic field unless there's an electrical current flowing through it. I mean, if you take a piece of iron and move it around where there's no magnetic field, it's not going to produce its own magnetic field, would it?

The mouse is right- pretty much everything produces a magnetic field. Its just that in most objects, the fields aren't aligned, so they pull in different directions and cancel each other out effectively. Iron and certain other materials are different in that you can force their fields to all point the way way.

The reason for the fields is electrons. They're moving about the nucleus, and they carry an electric charge. ANY moving charge produces a magnetic field. And vice versa.

[narf poit chez BOOM]

Iron and certain other materials are different in that you can force their fields to all point the way way.

yeah, but why?

[Fyron]

Because they are ferromagnetic elements. Such atoms are capable of remembering magnetic alignment, so materials made of them can be "magnets." Other elements and compounds are paramagnetic or diamagnetic. I forget which was which, but essentially, they are completely incapable of remembring a magnetic field. A field can be induced in them, but it is fairly weak (much weaker in one class than the other, though I forget which).

[Fyron]

Originally posted by Kamog:
I never understood this idea of the earth's magnetic poles moving around. How can the magnetic field, which was stable for a long period of time, suddenly reverse polarity? If the magnetic field is produced by the flow of molten material inside the earth, then it takes a tremendous amount of energy to change the direction of flow for so much mass. Where does this energy come from? Also, I thought that a flow of material will not produce a magnetic field unless there's an electrical current flowing through it. I mean, if you take a piece of iron and move it around where there's no magnetic field, it's not going to produce its own magnetic field, would it?

The magnetic field is not stable. It never has been, and never will be, unless the earth cools down and becomes a hunk of rock. The field is always in flux, due to the aforementioned movements of the liquid magma that is the bulk of the Earth's mass. The magnetic field of the Earth is always slowly changing. It reverses every few thousand years. This does not cause any significant increase in the amount of radiation that reaches the Earth's surface.