Physics - Lesson 1.3

Lesson 1.3 - Magnetic Earth
What are the effects of Earth's magnetic field?

 Vocabulary
  • compass
  • magnetic declination
  • Van Allen belts
  • solar wind
  • magnetosphere
  • aurora
Earth Producing Magnets
  • Since Earth produces a strong magnetic field, Earth itself can make magnets out of ferromagnetic materials.
  • If a ferromagnetic material is left in the same place for a long period, Earth's magnetic field can align the domains in the material and make it into a magnet.
   Earth's Magnetic Record
  • Earth's magnetic field also acts on rocks that contain magnetic material, such as rock on the ocean floor.
  • This creates a permanent record of Earth's magnetic field.
   Earth's Magnetic Record
  • The strength and direction of Earth's magnetic field has changed over time.
  • It has completely reversed direction every million years or so.






   Earth's Magnetic Field
  • Earth's magnetic field affects the movements of electrically charged particles in space.
  • These particles also affect Earth's magnetic field.
 










 Van Allen Belts
  • Between 1,000 and 25,000 kilometers above Earth's surface are two doughnut-shaped regions called the

    Van Allen Belts    .
  • These regions contain electrons and protons traveling at very high speeds.
  



Solar Wind
  • Other electrically charged particles in space come from the sun. Earth and other planets experience a solar wind.
  • The solar wind is a stream of electrically charged particles flowing at high speeds from the sun.
  





The Magnetosphere
  • The solar wind pushes against Earth's magnetic field and surrounds the field.
  • The region of Earth's magnetic field shaped by the solar wind is called the magnetosphere.
    





The Northern Lights
  • When charged particles get close to Earth's surface, they interact with atoms in the atmosphere.
  • This causes the atoms to give off light. A glowing region caused by charged particles from the sun is called an aurora.