Sunday, August 28, 2005

Spinning cores.

Finally earth scientists have announced that the earth's core is spinning at a different rate (faster) than the rest of the earth. That's a "duh." With an intense electromagnetic field that changes polarity and intensity with time, it simply had to have an "engine" and that engine has to be the (partially) liquid, iron core. Intuitively, we know that the magnetic field would be very stable if the core simply rotated at the same rate as the rest of the earth. Another intuitive awareness is that if the core is "liquid" (and we may have to redefine "liquid" for this intense heat and pressure zone), if the core is liquid, it is not "affixed" to the rest of the earth and might spin at the rate the earth once was spinning, or some measure of that spin. In earth science geo-speak, there once was a "big drop" of a lot of the iron in the molten ball now called "earth" and that group of heavy, molten metal (mostly iron), "fell" to the center and has remained molten. Since the geo-speak scientists generally agree the earth was once spinning faster than now, it stands to reason that the engine at the core is spinning faster than the outer shell. As I said, "duh."


It reminds me of the story of moon exploration. In the Kennedy years of "we're number two, Oh My Gawd" the dedicated race to beat the Russians at "something" produced a lot of moon debate. One of the big questions was whether the astronauts would be safe from moonquakes and some sort of moonquake might not knock over the lunar lander, preventing the people from a safe return. A large number of earth and astro scientists were gathered for a conference on this point at great expense to NASA. As learned papers were being delivered and much though given to moonquakes and possible fault zones on the moon, a not well known earth scientist from the back asked a simple question that was also an observation: "If there were fault lines on the moon creating moonquakes, wouldn't we see displacement of the pretty circles caused by meteor impact?" The learned group of scientists went silent for a moment and then began to laugh at the obvious that had been totally overlooked. Afterall, the moon would act similarily to the earth and an earthquake zone is accompanied by a fault line that displaces the surface, in some cases by many hundreds of miles. Any moonquake would also have such a surface feature and we would readily notice any displacement of those circles caused by meteor impact on the moon. It was one of those "duh" moments. Question answered, conference dissolved.


The next big scientific discovery about the earth core spin will be that the spin axis is not the same as the outer earth spin axis. That's another one of those "duh" moments. Of course we already know that. The magnetic pole is not at the spin pole. Gee, guess what that means. It means the object creating the magnetic field (the molten core) has a slightly different axis than the rest of the earth. Also, the fact of the reasonably regular flip flop of polarity would indicate a precession of spin/axis that slowly (in human terms) moves the polarity from north to south and back again.


Another "discovery" will be that the molten core represents a "fossil" energy. The spin is what the earth once was spinning at but our old earth has changed it's rate with time. So has the core, but the core responds slower to rotation changes. That gives us some evidence that the earth was once spinning faster than it is now and had a different spin axis orientation. Interesting. Using the data on core spin and axis, we can backtrack to see conditions relating to earth spin and axis in the past. I wonder how conditions on earth might have been with the faster spin and different axis. This fossil energy might even help us understand ancient events that helped form the earth and moon, even the solar system.


There are so many "scientific discoveries" that we already intuitively know. Many more than these few examples. Think. Don't believe only scientists know these things, you already know more than you pay attention to or realize.

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