Shackleton's first experience of the polar regions was as third officer on Captain Robert Falcon Scott's Discovery expedition of 1901-1904, from which he was sent home early on health grounds, after he and his companions Scott and Edward Adrian Wilson set a new southern record by marching to latitude 82°S. During the Nimrod expedition of 1907-1909, he and three companions established a new record Farthest South latitude at 88°S, only 97 geographical miles (112 statute miles or 180 kilometres) from the South Pole, the largest advance to the pole in exploration history. Also, members of his team climbed Mount Erebus, the most active Antarctic volcano. For these achievements, Shackleton was knighted by King Edward VII on his return home.