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Planet Earth

Detect abnormal changes in the earth’s magnetic field

Many satellites and spacecraft have been in trouble because of the abnormal changes in Earth’s magnetic field. This situation is believed to be indicative of a recurrence of the “geomagnetic inversion” phenomenon that was most recent 780,000 years ago.

Magnetic fields are believed to be related to processes that take place deep beneath the earth’s crust. The Earth’s core contains metal, in which its inner core is a sphere mainly in solid form and the outer core contains liquid. Due to the difference in temperature and pressure between the two nuclei, convection occurred, the flow of hot iron created an electric current and formed a magnetic field that protects the surface of our planet and all living things from it. solar radiation and dangerous cosmic radiation.

Simply put, the Earth is a magnetic dipole whose axis does not exactly coincide with the axis of rotation of the planet. An imaginary line connecting the two poles creates an angle of about 11.3 degrees to the Earth’s axis of rotation.

However, the Earth is not an ideal dipole. The planet’s magnetic field is heterogeneous, with anomalies due to the characteristics of deep underground structures and the varying degrees of magnetization of rocks in the earth’s crust. When the magnetic field is in the normal state, the charged particles of cosmic rays and solar wind (electrons and protons) start to slow down at a distance of 60,000 km from the Earth’s surface and cannot approach 1300 to 1500 km.

This is considered to be the limit of the radiation belt. The biggest anomaly is the South Atlantic – a large area, centered in South America, stretching to the southernmost tip of Africa, often referred to as the “Bermuda Triangle of the Universe.” . In this region, charged particles of cosmic rays can reach the Earth at a distance of 200 km.

This is especially dangerous for low orbit satellites and space telescopes – those located at this height. This leads to a malfunction of unprotected electronic equipment.

In 2007, for example, the first generation of Globalstar communications satellites in the United States went offline. In 2016, the Japanese Aerospace Agency’s Hitomi satellite was sent into space to observe the x-rays that had disappeared. When the Hubble Space Telescope flew over the anomalous region of the South Atlantic fell asleep.

In particular, on June 1, 2009, a plane of the French airline Air France flew from Rio de Janeiro in Brazil to Paris, disappeared from radar. Months later, the plane wreckage was discovered under the ocean. According to one theory, the problem arose due to an equipment failure in the South Atlantic anomaly region.

Unexpected discovery

In 2013, the European Space Agency (ESA) launched the constellation of Swarm satellites to study the planetary magnetic field. The three satellites recorded all the signals emitted by the core, mantle, earth’s and oceanic crust, as well as the main parameters of the ionosphere and the magnetosphere. ESA recently confirmed that, according to satellite data, the largest anomalous region on Earth has started to move, split in two and change in intensity. Earth’s magnetic field is strongest near the poles.

The weakest point is in the anomalous region of the South Atlantic. Scientific measurements made by the Swarm satellites have shown that magnetic field anomalies are increasing. According to an announcement on the ESA website, from 1970 to 2020, the anomalous limit of the South Atlantic moved westward at a rate of 20 km / year, and the strength of the magnetic field in This area has shrunk. About 24,000 to 22,000 nanotesla, or in other words, the magnetic field in the anomalous South Atlantic region has shrunk by more than 8% in just 50 years.

A few years ago, part of this anomalous region appeared to divide into a mass known as the “second center of minimum intensity” located in southwest Africa. Currently, in fact, this anomaly is divided into two parts, including the Brazilian anomaly and the Cape anomaly. This means that there will soon be another area that threatens the safety of satellites and space stations. Scientists have not yet been able to explain the cause of such a rapid change in magnetic fields in this part of the globe.

It is hypothesized that under the southern part of Africa, at the core-mantle border, there is a part with the reverse polarity, creating an unusual phenomenon. In this area, at a depth of about 2,900 km, there is a dense rock that geophysicists call a low speed rock, and geologists call it a superplume. Perhaps for some reason this rock started to move, affecting the abnormal region.

The cause of the above situation is not yet clear, but the nature of a change in the magnetic field is believed to come from a change deep in the Earth’s core. According to ESA, the greater possibility of the phenomenon is a sign that the Earth is about to “reverse” in terms of its magnetic field. More precisely, the two magnetic poles will be changed, from the South Pole to the North Pole and vice versa. Previous studies have shown that the Earth often reverses its magnetic pole every 250,000 years.

However, the most recent reversal occurred 780,000 years ago, which means that it went through the reverse cycle for many years, but this phenomenon did not happen. The fact that the Earth has been inverted several times shows that this phenomenon does not seem to constitute a danger for living organisms. However, with modern human civilization, we will inevitably suffer great damage in the positioning system – telecommunications because the Earth’s magnetic field is the “backbone” of the technological world.

Over the past 20 years, the Earth’s north magnetic pole has also started to move. This phenomenon creates serious problems for navigation systems at various levels – from shipping to maps on smartphones, since all of these devices are coordinate based. The exact geography of the magnetic pole is indicated by the tip of any compass. Geophysical data from satellites shows that the main cause of this phenomenon is also due to the anomaly, in this case the positive anomaly.

One of the regions with a strong magnetic field of water drop is located in northern Canada, the second – under the Siberian plateau. In particular, the “drop of water”

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