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Current Systems

Currents in a magnetosphere are like veins in the human body. They carry particles from one region to another. There are three main currents in a magnetosphere.

  • Chapman-Ferraro currents (in green)
  • cross-tail currents (in blue)
  • Field-Aligned currents (FAC's) in red)

The Chapman-Ferraro currents go around the outside of the magnetosphere and confine it.

Cross-tail currents pass through the center of the magnetotail, so that region is known as the "current sheet".

Field-Aligned currents show up sometimes (during magnetic storms), when particles need to take a short cut through a planet's atmosphere. These currents cause the aurora at the north and south p oles.

Return to "What is a Magnetosphere?"

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