What is the purpose of Earths magnetic field?

Question

I was told gravity and magnetic field are two different things.I was told its not the magnetic field but gravity that holds you on Earth.

Answer 1

to protect us from solar winds

Answer 2

there is no purpose it is just there... ok here it is .... the magnetic field is a homing beacon for extra terrestrials that go to earth every 2000 years to harvest their food supply which generally speaking is you and me.... have a nice day

Answer 3

Answering the second part first, yes gravity and the magnetic field are different. Gravity is a function of the mass of the body and provides an attractive force. The magnetic field is generated by an induced current formed due to the relative rotation of the inner and outer cores.

The main effect of the magnetic field is protection from the solar wind. This is a stream of charged particles known as plasma which are ejected from the sun at 400-750Km/s. The magnetic field deflects these particles and stops them from stripping away the earth's atmosphere. Some answers have suggested that it protects us from radiation, this is wrong.

Answer 4

No natural phenomenon has a "purpose" -- they only have effects.  The magnetic field is useful for driving compasses, forming the auroras at the poles (diverting radiation in the process), and dating rock formations.

Postscript: the response above this is total nonsense.

Answer 5

None... It's a natural phenomenon. Your question suggests that you think the earth somehow divined that a magnetic field would be useful, and thus created one. Man learned to use the magnetic field to determine direction.

Answer 6

to help keep you on it....

Answer 7

purpose? it wasnt built so it doesnt have a purpose

however, it does shield us against harmful electromagnetic radiation from the sun i think

Answer 8

The earth's molten core of iron was designed and created by God to provide a magnetic field that shields the earth from harmful solar radiation from the sun.... without which, the earth would be uninhabitable. It's one of the many features of earth that make it the only hospitable planet in possibly the whole universe for life to exist and to be able to observe the rest of the universe. Some animals, insects and birds also use it to navigate very precisely with a sort of lodestone or magnetite in their brains and a system in their brains to tell fluctuations and strengths of the magnetic fields generated by the earth. Also, designed and created by God.....pretty amazing.

Answer 9

so all planets and moons rotate around each other and sun with out crashing or going off path

Answer 10

The Earth's magnetic field, does not really have a purpose... It is the result of large electrical currents deep within the Earth.  These currents establish the magnetic field.  Without it, no life on Earth would be possible.  

The gravity field is a representation of the amount of force that the mass of the Earth exhibits upon you.

Answer 11

The region enclosed by earth's magnetic field is called the magnetosphere.It captures harmful high-energy charged particles from the sun and traps them in two belts named after their discoverer James Van Allen,that encircle the earth above the equator.

Further the magnetic field helps in navigation as the magnetic compass makes use of earth's magnetic field to indicate direction.

The spectacular Northern lights and Southern lights(aurora borealis and aurora australis) that appear high in the sky over poles are caused by charged solar-wind particles,entering the upper atmosphere being deflected towards the poles by the earth's magnetic field.

Answer 12

One reason I know is for navigation.  Not just for people, animals like birds and butterflies use it too!