Quote:
Originally Posted by CharlieO
...I was puzzled about the belief of Earth's core being iron and the only two related theories I knew anything about seemed illogical to me, even absurd.
...Pyrotex, Really impressed with your explanation. I always appreciate learning something new. Doing better than most at 76. You make a good teacher.
...Any other theories available?...
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CharlieO,
thanks for the complement. I enjoy teaching, especially to students who want to learn.
When one says that such-and-such a theory sounds absurd to one, one is generally obligated to explain WHY it sounds absurd. Give it a shot.
A "theory" is just an
explanation for the observed facts. Theories are judged according to
how well they explain the observed facts, and
how many of the observed facts they explain.
As time goes on, and more facts are accumulated, and the laws of nature better understood, some theories fall by the wayside because they do a relatively poor job of explaining the facts. Other theories rise to the fore and become "mainstream" and "accepted" because they do the best job of explaining the facts. This process is called Science. And it works.
New facts are constantly being observed, measured and discovered. New facts cannot disagree with old facts. A fact is a fact, after all. If you and I measure different atomic masses for the same atom, then one of us (at least) has made a mistake. That's why facts are generally the product of many, many repeated observations and measurements made by different people in different parts of the world over time. This process is called Verification. And it works.
Explanations CAN disagree with each other. I might say that Saturn's rings are the phosphorescent glow of a circular river of Mongo Fairies. You might say that they are particles of dust and ice held in orbit by Saturn's gravity. Two explanations. Two theories. So, we send the Cassini spacecraft to Saturn and accumulate facts. All the facts agree with your explanation and disagree with mine. Therefore MY "theory" ceases to be a real theory at all -- because it fails to explain the facts.
It is not often that two different and incompatible theories co-exist for any length of time. This is so because usually one or the other is much better at explaining the facts. Occassionally, there are not enough facts, or by some chance, the two theories are almost equally good at explaining what facts there are. This was the case with the Big Bang Theory versus the Steady State Theory in the 1950's and 60's. It was a very exciting time. Eventually new facts were observed, especially the Background Microwave Radiation. The Big Bang theory could successfully explain this. Steady State could not. Bye-bye Steady State.
As for the core of the Earth, there are vast amounts of observations made in many fields -- geology, earthwave tomography, astronomy, physics, chemistry, spectrometry, particle physics and radiation detection, mathematical modeling, computer simulations, wave mechanics, quantum mechanics -- that ALL have provided FACTS that must be considered when formulating any particular theory.
There are SOME people who choose only the facts that support their pet theory, and ignore the rest. These people are not "doing" Science. They are "doing" Play-Pretend.
Currently, the only theory that explains what we know about the Earth's core, and how it got to be there, is the theory I outlined above, which leads to the conclusion that the core is principally composed of iron. And that this was made possible by at least TWO natural mechanisms that differentiated matter by mass in the early stages of the Solar System, causing iron to be concentrated and accumulated by a factor of
thousands over its average percentage throughout the galaxy.
