£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terrestrial Magnetism and Field Reversals.ppt
1. A Brief Guide To Magnetism, Terrestrial Magnetic Field and Polar Reversals Jack Oughton
2. Definitions Dynamo - A system that uses electromagnetic induction to convert mechanical energy (motion) into a magnetic field Ferromagnetism is believed to be caused by magnetic fields generated by the electrons' spins in combination with a mechanism known as exchange coupling , which aligns all the spins in each magnetic domain. Curie temperature (Tc ) The temperature above which a ferromagnetic material loses its permanent magnetism. In minerals, lightning often flash-heats minerals above their Curie temperatures, effectively resetting the magnetic fields trapped in lava flows.
Notes de l'éditeur
* the Utopia impact injected so much heat into the Martian mantle that it drastically reduced the temperature difference driving the dynamo.
There is also true polar wandering which appears to be linked to plate movements and provides proof of continental drift . the above picture is Ellef Ringnes Island , the location of Earth's North Magnetic Pole in 1994
* An ESA Satellite program designed to give a more precise reading of the field and a representation of the magnetic field’s changes over time
The Orion Prophecy – one of the most influential psuedoscientific books