A Change Of Direction

Space Pages

Space Polls

Do you think the Universe was created by a Big Bang?

	Yes.
	No. There is another explanation.
	We'll never know the answer.

A Change Of Direction

Written by Kevin

Tuesday, 10 July 2007

A Change Of Direction
Evidence from the magnetism of ancient rocks shows that North and South poles swap places at irregular intervals averaging around 300,000 years. As the last swap happened nearly 800,000 years ago we may be due for another.

Some say changes in the Earth's magnetic field are indicators that the reversal is imminent; In Africa the field's direction is drifting about 1 degree, and the field strength has weakened globally by about 10 per cent in a little over a century.

However the rock record shows the magnetic field is always varying, and presently it is at its average intensity.

A reversal can take 5000 years to occur. In this time the may have six poles located around its equator. The threat to life would come from cosmic rays and solar winds being focused to the equatorial regions instead of deflected away!

< Prev