földmágnesség

Földmágnesség refers to the magnetic field generated by the Earth. This field is primarily produced by the movement of molten iron and nickel in the Earth's outer core. It extends from the Earth's interior out into space, forming a protective shield known as the magnetosphere. The magnetosphere deflects most of the harmful charged particles from the sun, which would otherwise strip away the atmosphere.

The Earth's magnetic field is not static; it fluctuates in strength and direction over time. The magnetic poles, which are near the geographic poles, do not perfectly align and also wander. Evidence suggests that the Earth's magnetic field has reversed its polarity many times throughout geological history. These reversals are not instantaneous and can take thousands of years to complete.

The study of földmágnesség, or geomagnetism, is important for various scientific disciplines. It aids in understanding the Earth's internal processes, navigation using compasses, and the behavior of charged particles in space. Furthermore, the magnetic field plays a role in phenomena like the aurora borealis and aurora australis, which are visible displays of light in the sky caused by the interaction of charged particles with atmospheric gases. Paleomagnetism, a subfield of geomagnetism, analyzes the magnetic signature preserved in rocks to reconstruct past magnetic field directions and study plate tectonics.