What is the direction of the Earth s magnetic field, what is the direction of the geomagnetic field?

Geographic South Pole to Geographic North Pole.

The direction of the geomagnetic field is from south to north. The Earth's magnetic field is the magnetic field distributed in the space around the Earth. The dipole type approximates placing a magnet rod in the center of the earth, with the north n pole of the geomagnetic field near the geographic south pole and the south s pole of the geomagnetic field near the geographic north pole.

The magnetic pole does not exactly coincide with the geographical pole, and there is a magnetic declination. The distribution of magnetic field lines is characterized by the fact that the direction of the magnetic field near the equator is horizontal, and the near poles are perpendicular to the earth's surface. The magnetic field is weakest at the equator and the strongest at the poles.

The magnetic field on the earth's surface changes over time due to various factors.

Overview

The geomagnetic field consists of two parts: the basic magnetic field and the variable magnetic field. The basic magnetic field is the main part of the geomagnetic field, which originates from the interior of the solid earth, is relatively stable, and belongs to the part of the static magnetic field. The variable magnetic field includes various short-term changes in the geomagnetic field, which mainly originate from the outside of the solid earth and is relatively weak.

The magnetic field of earth change can be divided into two types: calm change and disturbance change.

Marching and sailing use the action of the geomagnetic field on the compass to orient themselves. One can also look for mineral deposits based on the characteristics of the geomagnetic field distributed on the ground. Changes in the geomagnetic field can affect the propagation of radio waves.

When the local magnetic field is strongly disturbed by sunspot activity, long-distance communication will be seriously affected or even interrupted.

In the absence of a geomagnetic field, a strong stream of charged particles from the sun, usually called the solar wind, would not be deflected by the geomagnetic field, but would shoot directly at the earth. Under the bombardment of such energetic particles, the composition of the Earth's atmosphere may not be what it is now, and life will not be able to exist. So the geomagnetic field is a very important umbrella for us.

The direction of the geomagnetic field is from the north pole of the earth to the south pole of the earth.

The earth itself is a huge magnet, and the magnetic field around the earth is called the geomagnetic field; The magnetic north pole is near the geographic south pole; The geomagnetic south pole is near the geographic North Pole, but it does not coincide.

The earth itself is a huge magnet, and the magnetic field around the earth is called the geomagnetic field, the geomagnetic north pole is near the geographical south pole, and the geomagnetic south pole is near the geographic north pole, so the direction of the geomagnetic field is from the geomagnetic north pole to the geomagnetic south pole.

The origin of the Earth's magnetic field

The hypotheses about the origin of the geomagnetic field can be divided into two categories: the first type of hypothesis is based on existing physical theories; The second type of hypothesis takes a unique approach, arguing that for a cosmic object such as the earth, there are special laws that are different from the existing known theories.

The first type of hypotheses include the rotational charge hypothesis, the geomagnetic field hypothesis with the earth's core as a precondition, the drift current hypothesis, the thermal effect hypothesis, and the Hall effect hypothesis.

1) There is the rotational charge hypothesis that there is an equal amount of opposite-sex charge on the earth, one distributed in the interior of the earth and the other distributed on the surface of the earth, and the charge rotates with the earth, thus creating a magnetic field.

2) The geomagnetic field hypothesis, which presupposes the earth's core, holds that the formation of electric current in the earth's core should occur by induction when the metal material in the earth's core moves vortex in the magnetic field. At the same time, the field in the form of the electric current itself is a continuous regenerative magnetic field, as in the case of a generator.

Direction of magnetic field: The direction of the magnetic field force at a point in the magnetic field of the north pole of the small magnetic needle is specified as the direction of the electromagnetic field.

The direction from the North Pole to the South Pole is from the South Pole to the North Pole inside the magnet, and can be expressed as the tangent direction of the magnetic inductance line or the direction pointed by the North Pole when the small magnetic needle placed in the magnetic field is at rest!

The north and south poles of the magnetic field are exactly the opposite of the north and south poles of geography, and there is a declination angle between the two poles at one end, which is called magnetic declination! The magnetic declination is constantly changing slowly! Mastering the change in magnetic declination is of great significance for applying compass pointing!

One of the first drawings of the magnetic field by René Descartes, 1644.

Although magnets and their mysterious magnetic properties have long been known to mankind, one of the first scholarly treatises was written by the French scholar Pierre de Maricourt in 1269 AD[note 3]. DeMarek carefully marked the orientation of the iron needle at various locations near the block magnet, and from these marks, a number of magnetic field lines were traced.

He found that these magnetic field lines meet at opposite ends of the magnet, just as the Earth's meridians meet at the north and south poles. Therefore, he called these two positions the magnetic poles. Almost three centuries later, William Gilbert argued that the Earth itself is a large magnet, with two poles at the South and North poles.

Published in 1600, Gilbert's magnum opus, de Magnete, established magnetism as an orthodox science.

In 1824, Simon Poisson developed a physical model that was more capable of describing the magnetic field. Poisson believed that magnetism is generated by magnetic charges, with similar magnetic charges repelling each other and different magnetic charges attracting. His model is a complete analogy to modern models of electrostatics; A magnetic charge produces a magnetic field, just as an electric charge produces an electric field.

This theory can even correctly store energy in a magnetic field.