It’s amazing to me that the brain also generates magnetic fields outside of our heads. Perhaps this is what some people call the ‘aura’ of a person but I’ll leave that for another day. Proof of these magnetic fields are evidenced in the use of very sensitive magnetic sensors which are placed on the head, usually by neuroscientists conducting experiments, which pick up electrical wave lengths via the magnetic fields they produce. Neuroscientists can look at the graph produced by the EEG (electroencephalogram) and make diagnoses like epilepsy or sleep disorders. Magnetoencephalogram (MEG) headset technology is able to detect magnetism deeper in the brain (without any ill effects on the subject) and can give a more detailed picture of the cognitive processes in different areas in the brain whilst performing different activities.
Magnetoencephalogram (MEG) 3D printed headset developed by Nottingham University.
Over a series of posts I’d like to talk about lots of different aspects of this Natural force of Nature.From Geomagnetism to the Magnetosphere and from historic Navigational compasses to Magneto-reception in animals. But first I’d like to talk about the biggest magnet on earth : Planet Earth.
The earths North and South poles exist as a result of molten iron swirling miles beneath our feet.This liquid outer core at the centre of the earth is very active and flows in random patterns a bit like our weather.What generates this continuous movement, is the spin of the earth in space, which is 1000 miles per hour at the equator.Because of the spinning, a motor like effect is produced and in turn electrical currents are generated by the swirling iron.It’s these electrical currents which are responsible for creating the magnetic fields which polarise the Earth into a giant magnet with a North and a South pole.
NOAA has a very cool website about declination and this page shows where the north pole has moved over the last 400 years which was painstakingly generated from shipping logs collected from hundreds of historic journeys. This illustration shows the movement of magnetic north over the last 100 years. https://maps.ngdc.noaa.gov/viewers/historical_declination/
As well as orienting the earth’s magnetic field lines from north to south, the magnetic field also extends out beyond the earths atmosphere creating the Magnetosphere. Without the Magnetosphere, life on earth wouldn’t have evolved as we know it today because it shields us from the suns harmful radiation as this illustration shows.
This is also the reason we get the Northern Lights, more on this in the next post. I’ll leave you with this rather understated quote:
“I happen to have discovered a direct relation between magnetism and light, also electricity and light, and the field it opens is so large and I think rich.” — Michael Faraday (1899)
Hi, my name is Richard currently a student on the Art & Science course at CSM. On this platform I’d like to share what I find fascinating about magnetism and how this invisible force of nature influences our lives. I’ll be using examples of my work as well as research I’ve discovered which I hope you’ll find interesting.