The Ship’s Compass – A History
The Earth has a core of molten iron which provides it with a strong magnetic field. This is not true of all planets, and it transpires that this phenomenon is vital to life. The magnetic field shields us from much of the sun’s more harmful radiation, without which our world would soon be reduced to a dry, rocky wilderness. It also helps many animals, such as migrating birds and whales to navigate, and has long been used by humans to help them find their way. Early navigators
