Earths Magnetic Field

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Earth’s Magnetic Field
Introduction
Earth's magnetic field is one of the world's most complicated features. It started to be observed in 1845 by a scientist named Carl Friedman Gauss (Sarfati). The magnetic field is generated inside of the earth's core and there are many scientists who still debate over how it was first created. There are also many arguments about the many changes that the field has gone through in it's existence. These arguments are mostly either for a young-earth model or an old earth model. History of the magnetic filed

Earth's magnetic field is a field of electric current that is conducted from the earth's solid inner core through the liquid outer core (Richard). The electrical current goes around the earth and through it at the north and south poles. The north pole was first discovered by James Ross in 1831 (nasa.gov). No one visited it again until the early 1900s. "In 1904, Roald Amundsen found the pole again and discovered that it had moved--at least 50 km since the days of Ross," (nasa.gov). The north pole continued to move at an average of about 10 kilometers per year in the twentieth century (nasa.gov). More recently scientist Larry Newitt of the Geological Survey of Canada has said that it has been moving an average of 40 kilometers every year (nasa.gov).

The past of earth's magnetic field can be studied by past lava eruptions that have hardened. "When grains of the common magnetic mineral magnetite in volcanic lava or ash flows cool below its Curie point of 570°C (1060°F), the magnetic domains partly align themselves in the direction of the earth’s magnetic field at that time. Once the rock has fully cooled, the magnetite’s alignment is fixed," (Sarfati). The Curie point of a substance is the temperature at which it loses its magnetism, so the lava must cool below this point before the magnetite can align(Sarfati). Using these records scientists have seen that the earth's pole have switched several times in the...
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