Such a phenomenon as magnetism has been known to mankind for a very long time. It got its name thanks to the city of Magnetia, which is located in Asia Minor. It was there that a huge amount of iron ore was discovered. The very first mention of the unique properties of a magnet can be found in the works of Titus Lucretius Cara, who wrote about this in the poem "On the nature of matter," around the 1st century BC.
Since ancient times, people have found application for the unique properties of iron ore. One of the most common devices, the action of which was based on the attraction of metals, was a compass. Now it is very difficult to imagine various industries in which simple magnets and electromagnets would not be used.
Earth's magnetic field is the area around the planet that protects it from the harmful effects of radioactive solar radiation. Scientists argue about the emergence of this field to this day. But most of them believe that it arose thanks to the core of the Earth. The center of our planet has a liquid external and solid internal component. During rotation, the liquid part of the core moves, the dressed up electric particles move and a so-called magnetic field is formed.
Earth's magnetic field is also called the magnetosphere. The concept of “magnetism” is a comprehensive and global property of nature. At the moment, it is impossible to create a fully completed theory of solar and terrestrial attraction, but now science is trying to figure it out in many ways and it is able to give quite convincing explanations to various aspects of this complex phenomenon.
Recently, scientists and ordinary citizens have been largely concerned about the fact that the Earth's magnetic field is gradually weakening its influence. It has been scientifically proven that over the past 170 years the magnetic field has been steadily weakening. This makes you think, as it is a certain kind of shield that protects the Earth and wildlife from the terrible radiation effect of sunlight. The Earth’s magnetosphere resists the flow of all such particles that fly toward the poles. All these flows are trapped in the upper atmosphere at the poles, forming a wonderful phenomenon - the northern lights.
If suddenly the Earth’s magnetic field disappears or weakens significantly, then everything on the planet will be under the direct influence of cosmic and solar radiation. In turn, this will lead to radiation diseases and damage to all living organisms. The result of such a disaster will be terrible mutations or complete death. To the great relief, such a development is unlikely.
Paleomagnetologists have been able to provide fairly reliable data that the magnetic field is constantly fluctuating, and the period of such oscillations varies. They also compiled an approximate curve of field fluctuations and found out that at the moment the field is in a falling position and will decrease for another couple of thousand years. Then it will again intensify over 4 thousand years. The last maximum value of the magnetic field attraction was at the beginning of the current era. The reasons for this instability are put forward the most diverse, but there is no specific theory on this subject.
It has long been known that many magnetic fields have a negative effect on living organisms. For example, experiments performed on animals have shown that an external magnetic field can delay development, slow down cell growth, and even change the composition of blood. That is why magnetic storms lead to a deterioration in the health of weather-dependent people.
For humans, the Earth’s safe magnetic field is a field with a strength value of not more than 700 oersteds. It is worth noting that this is not about the actual magnetic field of the Earth, but about the electromagnetic fields that are formed during the operation of any radio and electrical device.
The physical side of the process of the influence of the Earth’s magnetic field on humans is still not entirely clear. But it was possible to find out what it affects the plants: germination and further growth of seeds directly depend on their initial orientation with respect to the magnetic field. Moreover, its change can either accelerate or slow down the development of the plant. It is possible that someday this property will be used in agriculture.
Earth's magnetic field is the force of its attraction. In some places, it fluctuates, but the average figure is 0.5 Oersted. In some places (in the so-called magnetic anomalies), the tension increases to 2 Oe.