human representations of the outside world began to develop from mid-14th century.Later, Rene Descartes, the great mathematician, suggested that our planet formed from a lump of mass, which was similar to the first, the bright sun, but then cooled down.In this connection, hidden in the depths of the "core of the Earth."But check this assumption at the time was not possible.
Subsequently, Newton found a French expedition of scientists confirmed that the pole of the planet somewhat flattened.From this it follows that the earth is a ball not the correct form.Buffon (French naturalist), supporting this statement suggested that this may be the case if the bowels of the planet has a molten structure.Buffon in 1776 speculated that in ancient times there was a collision of the sun and some of the comet.Comet this "knocked out of the light of a certain mass of matter.This mass is gradually cooling down, was the Earth.
hypothesis Buffon started checking physics.According to the thermodynamic laws, no process can not continue indefinitely: since, as will be exhausted its energy, it will stop.In the 19th century it was made some calculations.Mathematician and physicist Lord Kelvin in England found that in order to cool down, to lose a lot of energy, and cease to be a molten mass, becoming the way it is now, you need about a hundred million years.Geologists, in turn, pointed out that the age of rocks much more.Furthermore, in the 19th century it was already discovered the phenomenon of radioactivity.Thus, it became clear that the collapse of the elements necessary for many hundreds of millions of years.
Until recently it was believed that the Earth's core is a completely smooth ball right shape (like a cannon nucleus).In the eighties, it was invented so-called seismic tomography.With it, scientists have found that the Earth's core has its own topography.The thickness of the surface proved to be different.In some areas, it is one hundred and fifty kilometers, and on the other - up to three hundred and fifty.
According to information obtained by means of seismic waves, liquid (molten) is the Earth's outer core (layer having uneven terrain).The inner part is a "hard" because the entire planet is under pressure.Calculate the pressure of the outer part of the order of 1.3 million atmospheres.In the center of pressure is increased to three million atmospheres.The core temperature of the Earth about 10,000 degrees.The weight of a cubic meter of a substance from the bowels of the planet - about twelve or thirteen tons.
between the sizes of parts that includes the core of the Earth, there is a definite relationship.The inner part of the order of 1.7% of the mass of the planet.The outer part - about thirty percent.The material from which the greater part consists obviously diluted somewhat relatively easy likely sulfur.Some experts suggest that this element is about fourteen percent.