How do Magnetic Storms Form? All magnetic fields have a direction. The solar wind’s field can point in all sorts of directions: towards Earth, away from Earth, towards the north, towards the south, and even towards the east and west. The actual direction of the field when a Coronal Mass Ejection (CME) comes crashing into Earth’s magnetosphere is very important. If it’s directed southward, scientists have found that disturbances in the solar wind, like CMEs, can penetrate Earth’s protective shield and cause magnetic storms. If the solar wind’s magnetic field has some other direction, like northward, then conditions are mild. The direction of the field acts like an electric switch: northward the switch is off; southward it is turned on. [Click here to see a Magnetic Storm Animation] (Animation, 6.63MB) Angela Cheyunski/Honeywell Max-Q Digital Group for NASA