The magnetic South Pole was first reached during Shackleton's British Antarctic Expedition (1907-1909) by Professor Edgeworth David and Sir Douglas Mawson (Australian geologists) and Alistair Mackay who claimed the surrounding Victoria Land for the British Crown. At that time the magnetic pole lay within the Antarctic continent at latitude 71.6°S and longitude 152°E. Today it lies far out to sea at latitude 65°S and longitude 139°E. and travels 10 to 15 km north-westerly each year. Electric currents and the rolling motion of the liquid iron core of the Earth dictate the position of the magnetic poles. The pole wanders daily in a roughly elliptical path