Ross, Sir James Clark (1800–1862), a British Arctic and Antarctic explorer. In 1839 Ross commanded an expedition searching for the South Pole. It reached 78º 10´ S., a latitude that was not passed until 1900. He was knighted on his return in 1843. Ross Sea, Ross Ice Shelf, and Ross Island in the Antarctic are named for him.
Ross was born in London. He entered the navy in 1812, and in 1818 accompanied his uncle, John Ross, in search of a northwest passage to Asia. Between 1819 and 182 7 he sailed with William Edward Parry on four expeditions to the Arctic. They reached the northern shores of the island of Svalbard in 1827. Their latitude of 82º 45' N. was the farthest point north attained to that time. On another voyage with his uncle, 1829–33, Ross determined the position of the north magnetic pole.