Sir James Clark Ross (1800-1862), British explorer who discovered the position of the magnetic North Pole. Born in London, Ross entered the British navy at the age of 12. In 1818 he took part in an Arctic voyage led by his uncle, Captain John Ross, in search of the Northwest Passage between the Atlantic and Pacific oceans. Between 1819 and 1827 James Ross participated in four Arctic expeditions led by British explorer Sir William Edward Parry. These voyages included exploration of Lancaster Sound, Melville Island, and Prince Regent Inlet, as well as an unsuccessful attempt to reach the North Pole from the archipelago of Spitsbergen (now Svalbard), off the coast of Norway.

Ross was second in command on his uncle’s second Arctic voyage, which lasted from 1829 to 1833. When their ship became icebound, the younger Ross led a series of overland expeditions. In 1831, on one such expedition, he discovered the position of the magnetic North Pole, then in Boothia Peninsula. The magnetic north pole has shifted location over time and is now in the vicinity of Ellef Ringnes Island in the Queen Elizabeth Islands of the Northwest Territories, Canada (see Magnetic Pole).

Between 1835 and 1838 Ross worked on a magnetic survey of Great Britain, and in 1839 the British government placed him in command of an Antarctic expedition in search of the magnetic South Pole. On this voyage, Ross made several important geographical discoveries, sighting and naming Victoria Land and exploring present-day Ross Sea and Ross Island (both named for him). Although he failed to reach the South Pole, Ross broke the record set by British navigator James Weddell for the farthest southern exploration. Ross was knighted upon his return to England in 1843.

In 1848 Ross made an Arctic voyage to search for British explorer Sir John Franklin, who had not returned from an expedition undertaken three years earlier to discover the Northwest Passage. Ross’s expedition did not succeed in finding Franklin. Ross is the author of A Voyage of Discovery and Research to Southern and Antarctic Regions (1847).