This figure shows a model of the Earth's magnetic field being generated within the Earth. Click on image for full size version (40K GIF) Image provided courtesy of Gary A Glatzmaier (Los Alamos National Laboratory) and Paul H Roberts (University of California, Los Angeles). For more detail about the simulated geomagnetic reversal see Nature (1995) 377, 203-209.

Scientists believe, although it is not certain, there are two essential ingredients for generating a magnetic field. Those two ingredients are

• magnetic material
• currents

It is believed that a planet, or a star, can generate a magnetic field if it has both of the two ingredients above. It must have enough magnetic material, and it must have currents moving inside the magnetic material. If a planet does not have enough of either of these two ingredients, it will not have a magnetic field. Planets which do not have magnetic fields include Venus (moves very slowly), and Mars (most the iron is on the surface, and not molten).

This figure shows a model of the Earth's magnetic field being generated within the Earth. Click on image for full size version (40K GIF) Image provided courtesy of Gary A Glatzmaier (Los Alamos National Laboratory) and Paul H Roberts (University of California, Los Angeles). For more detail about the simulated geomagnetic reversal see Nature (1995) 377, 203-209.

Scientists think, although not certain, there are two essential ingredients for generating a magnetic field. Those two ingredients are

• magnetic material
• currents

It is believed a planet, or a star, can generate a magnetic field if it has both of the two ingredients above. It must have enough magnetic material, and it must have currents moving inside the magnetic material. If a planet does not have enough of either of these two ingredients, it will not have a magnetic field. Planets which do not have magnetic fields include Venus (moves very slowly), and Mars (most the iron is on the surface, and not molten).

This figure shows a model of the Earth's magnetic field being generated within the Earth. Click on image for full size version (40K GIF) Image provided courtesy of Gary A Glatzmaier (Los Alamos National Laboratory) and Paul H Roberts (University of California, Los Angeles).

Scientists believe there are two essential ingredients for generating a magnetic field. Those two ingredients are

• magnetic material
• currents

It is thought a planet, or a star, can generate a magnetic field if it has both of the two ingredients above. It must have enough magnetic material, and it must have currents moving inside the magnetic material. If a planet does not have enough of either of these two ingredients, it will not have a magnetic field. Planets which do not have magnetic fields include Venus (moves very slowly), and Mars (most the iron is on the surface, and not molten).