The Earth's magnetic field extends far out beyond the atmospere, creating the
magnetosphere. The size of the magnetosphere fluctuates with the solar wind. The presence of the magnetic field
shields the Earth from the charged particles of solar wind plasma, and prevents them from directly hitting Earth.
But, there are mechanisms that allow this solar wind plasma to enter the
Earth's magnetosphere esspecially during magnetic storms. During these very
active periods, satellites, and ground power grids can be severely damaged.
The outer boundary of the magnetosphere is called the magnetopause.
Beyond the sunny side of the magnetopause, there is a bow shock, a
result of the solar wind moving at supersonic speed. The solar wind squishes
the day side of the magnetosphere, and creates a very long tail on the night
side. Between the Bow shock and the magnetopause, we find the magnetosheath.
Main regions inside the magnetosphere are the tail lobes, plasmasheet, the
radiation belts and the plasmasphere.