EARTH AS A MAGNET

The Magnet in Earth

The earth has an inner core that is made of pure iron, when this core is moving it creates an electric current that causes an invisible magnetic field to appear. You can think of the core as a magnet, the south end is pointing at the North Pole and the north end is pointing at the South Pole. This is based on the “opposites attract” rule, because of this rule the needle on a compass always points towards the North Pole. The needle has to be made of a lightweight magnet or the Earth's field won’t have enough strength to move it. The diameter of the earth is approximately 8000 miles; this means the magnetic field is very weak and has to travel a long way before it has any affect.  

When one sees a compass and the needle is pointed straight north, they assume that the needle is pointing straight towards the North Pole, this assumption is wrong. In reality, the needle is pointing at a slight angle because of the tilt. The north magnetic pole is currently located near Bathurst Island in northern Canada and the South magnetic pole is located near the continent of Antarctica. Every year, the poles can switch there places up to 10km, so where they are now they won’t be exactly there next year.  This is caused by climate change and other factors, preventing the magnetic field to stay in one place.

Present Day

In current times, the magnetic field has weakened by 10%. This could be because of rising sea level or climate change. However, geologists and scientists have said that it is not a matter that society should take seriously. Upon their research they have found that the earth’s magnetic field has gone through worse situations.

The Northern Lights

The Northern Lights are a wonder that occur over northern Scandinavia Island, the southern tip of Greenland and continuing over northern Canada. They are geographical located 2500km, centre in the

North magnetic pole. Even though we associate the lights only in winter time, they are present all year round.

How are the Northern Lights made? Well, it all begins with the sun and a cloud of gas called, ejection. When one of these ejections, reaches earth, it automatically collides with the magnetic field. Once collision happens, it causes currents of charged particles to flow to the poles of the earth. These particles are then converted into energy and mix with oxygen and nitrogen atoms to produce a marvellous light show.

References:

1.        Earth's Inconstant Magnetic Field - NASA Science. NASA Science. Retrieved February 25, 2012, from http://science.nasa.gov/science-news/science-at-nasa/2003/29dec_magneticfield/

2.        Brain, M. HowStuffWorks "Earth's Magnetic Field". HowStuffWorks "Adventure". Retrieved February 25, 2012, from http://adventure.howstuffworks.com/outdoor-activities/hiking/compass1.htm

3.        What are the northern lights?(Everyday Mysteries: Fun Science Facts from the Library of Congress). Library of Congress Home. Retrieved February 25, 2012, from http://www.loc.gov/rr/scitech/mysteries/northernlights.html