We know that Earth s magnetic field is always shifting in its direction and its strength. Just how quickly these changes are happening is of great interest, considering this planetary feature keeps us all protected from violent cosmic radiation.
Further evidence of 200 million-year cycle for Earth s magnetic field newswise.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from newswise.com Daily Mail and Mail on Sunday newspapers.