The Earth's magnetic field is believed to be generated by electric currents in the conductive iron alloys of its core, created by convection currents due to heat escaping from the core.
The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma consists of mostly electrons, protons and alpha particles with kinetic energy between 0.5 and 10 keV. Embedded within the solar-wind plasma is the interplanetary magnetic field. As Earth cruises through the black sea of space at about 67,000 mph (108,000 km/h), the planet's magnetic field pushes aside solar wind — the constant stream of plasma particles ejected by the sun — the same way the bow of a speeding motorboat pushes aside water.
The Earth's magnetic field serves to deflect most of the solar wind, whose charged particles would otherwise strip away the ozone layer that protects the Earth from harmful ultraviolet radiation.
A Van Allen radiation belt is a zone of energetic charged particles, most of which originate from the solar wind, that are captured by and held around a planet by that planet's magnetic field. Earth has two such belts and sometimes others may be temporarily created.
An aurora (plural: auroras or aurorae), sometimes referred to as polar lights, northern lights (auroraborealis), southern lights (aurora australis), is a natural light display in the Earth's sky, predominantly seen in the high-latitude regions (around the Arctic and Antarctic). Charged particles from the sun strike atoms in Earth's atmosphere, they cause electrons in the atoms to move to a higher-energy state. When the electrons drop back to a lower energy state, they release a photon: light. This process creates the beautiful aurora, or northern lights.
Simulation of the interaction between Earth's magnetic field and the interplanetary magnetic field. Earth is largely protected from the solar wind, a stream of energetic charged particles emanating from the Sun, by its magnetic field, which deflects most of the charged particles.
What causes an aurora?
What does Earth do to the planet's magnetic fieldpushes aside solar wind?
