The Earth is a great natural magnet . It has north and south magnetic poles, a magnetic axis and a magnetic field. Its magnetic field extend far out into space.
Above the Earth, 4000 miles or 6400 kilometers, the intensity of Earth’s magnetic field is still as great as one-eight of the gravity at the Earth’s surface. The magnetic field of the Earth is not yet fully-understood. It is thought that it arises from electric current that are circulating in the Earths molten outer core.
We cannot see the magnetic field as it is invisible. We can imagine it as linepatterns that loop from one pool to the other pole of the planet. These field lines are parallel to the surface near the earth equator. They bend and converge as the field lines approach the two magnetic poles.
These magnetic fields helps shield the planet Earthfrom the harm of radiation. They deflect or capture the charged particles streaming from the Sun.
This event forms the two vast zones of radiation. It is called the Van Allen radiation belts. These radiations surrounds the Earth. Solar wind, the storm of particles flowing from the sun, distorts the shape of the magnetic field into a long “tail” just like what we see on a comet.
Our planets magnetic field are very much useful for some living organisms. Fishes, Sea turtles, migrating Birds and others use these magnetic fields for their navigation purposes. We humans cannot sense these fields naturally but we can make use of it by detecting these magnetic fields using a compass.