Which scientist explained correctly about the center of the earth

In fact, the eastern hemisphere of the inner core may actually be melting. Geoscientists recently discovered that the inner core itself has a core—the inner inner core. This strange feature differs from the inner core in much the same way the inner core differs from the outer core.

Scientists think that a radical geologic change about million years ago caused this inner inner core to develop.

The crystals of the inner inner core are oriented east-west instead of north-south. Scientists think the iron crystals may even have a completely different structure not hcp , or exist at a different phase. Magnetism in the outer core is about 50 times stronger than it is on the surface. But in the inner core, the temperature is so high the magnetism of iron is altered.

Once this temperature, called the Curie point , is reached, the atom s of a substance can no longer align to a magnetic point. Variations in rotation, conductivity, and heat impact the magnetic field of a geodynamo.

Mars, for instance, has a totally solid core and a weak magnetic field. Venus has a liquid core, but rotates too slowly to churn significant convection currents. It, too, has a weak magnetic field. It rotates steadily, at a brisk 1, kilometers per hour 1, miles per hour at the Equator.

The liquid iron in the outer core is an excellent electrical conductor, and creates the electrical current s that drive the magnetic field. The energy supply that drives convection in the outer core is provided as droplets of liquid iron freeze onto the solid inner core. Solidification releases heat energy. This heat, in turn, makes the remaining liquid iron more buoyant.

Warmer liquids spiral upward, while cooler solids spiral downward under intense pressure: convection. It protects the planet from the charged particles of the solar wind. As the liquid outer core moves, for instance, it can change the location of the magnetic North and South Poles.

The magnetic North Pole moves up to 64 kilometers 40 miles every year. Geomagnetic pole reversal s, for instance, happen about every , to , years. Geoscientists cannot study the core directly. All information about the core has come from sophisticated reading of seismic data, analysis of meteorites, lab experiments with temperature and pressure, and computer modeling.

Most core research has been conducted by measuring seismic waves, the shock wave s released by earthquake s at or near the surface. The velocity and frequency of seismic body waves changes with pressure, temperature, and rock composition. In fact, seismic waves helped geoscientists identify the structure of the core itself. S-waves are unable to transmit through fluids or gases. In the 20th century, geoscientists discovered an increase in the velocity of p-wave s, another type of body wave, at about 5, kilometers 3, miles below the surface.

The increase in velocity corresponded to a change from a liquid or molten medium to a solid. This proved the existence of a solid inner core. Most meteorites are fragments of asteroid s, rocky bodies that orbit the sun between Mars and Jupiter. Asteroids formed about the same time, and from about the same material, as Earth.

Finally, he correctly proposed that Earth's motion through space caused the retrograde motion of the planets across the night sky planets sometimes move in the same directions as stars, slowly across the sky from night to night, but sometimes they move in the opposite, or retrograde, direction. In it, Copernicus established that the planets orbited the sun rather than the Earth. He laid out his model of the solar system and the path of the planets. He didn't publish the book, however, until , just two months before he died.

The church did not immediately condemn the book as heretical, perhaps because the printer added a note that said even though the book's theory was unusual, if it helped astronomers with their calculations, it didn't matter if it wasn't really true, according to Famous Scientists.

It probably also helped that the subject was so difficult that only highly educated people could understand it. The Church did eventually ban the book in Copernicus died on May 24, , of a stroke. He was He was buried in Frombork Cathedral in Poland, but in an unmarked grave. Remains thought to be his were discovered in In , researchers announced that a skull found in Frombork Cathedral did belong to the astronomer.

By matching DNA from the skull to hairs found in books once owned by Copernicus, the scientists confirmed the identity of the astronomer. Polish police then used the skull to reconstruct how its owner might have looked.

Nicolaus Copernicus died on May 24, in what is now Frombork, Poland. He died the year his major work was published, saving him from the outrage of some religious leaders who later condemned his heliocentric view of the universe as heresy. It was not until the early 17th century that Galileo and Johannes Kepler developed and popularized the Copernican theory, which for Galileo resulted in a trial and conviction for heresy.

But if you see something that doesn't look right, click here to contact us! Subscribe for fascinating stories connecting the past to the present. Alexander Graham Bell, best known for his invention of the telephone, revolutionized communication as we know it.

His interest in sound technology was deep-rooted and personal, as both his wife and mother were deaf. Galileo Galilei is considered the father of modern science and made major contributions to the fields of physics, astronomy, cosmology, mathematics and philosophy.

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And the key discoveries were made by two scientists who, shamefully, were never even nominated for a Nobel Prize: British geologist Richard Oldham and Danish seismologist Inge Lehmann. But many waves — sound, for example — travel through the body of a material. They vibrate in the direction of movement, causing the Earth to squash up and expand as they pass through. P-waves travel rapidly — around 5km per second in a rock like granite, and up to 14km per second in the densest parts of the mantle.

The P-waves shoot ahead, while the S-waves follow behind at around half the speed. Both types of wave will be detected by seismometers, which are used to measure vibrations in the ground, all over the Earth.

But where the waves pass through the core to reach a distant measuring station, there is a so-called shadow zone.

As early as , Richard Oldham realised the implications of this odd shadow. Oldham spent most of his career with the Geological Survey of India, often working in the Himalayas.

When he retired to the UK in , he made use of the data accumulated over the previous few years to probe the interior of the Earth. He realised that the observed P-wave and S-wave behaviour could be explained if the centre of the Earth was liquid.

In such a case, P-waves would be refracted by the liquid, bending as light does when it moves from water to air, leaving a distinctive shadow. S-waves, by contrast, would be stopped entirely by a liquid core. The refraction of the P-waves by the dense liquid in the centre of the Earth should have produced a total shadow. By studying data passing through the planet from a New Zealand earthquake Lehmann proposed that these waves were being reflected off the boundary between an inner solid core and the outer liquid.