Editing Nathaniel Palmer (section)

==Sealing career and Antarctic exploration==
During the 1810s the hides of [[Antarctic Ocean]] seals were highly valued as items for trade with [[China]]. Palmer served as second mate on board {{ship||Hersilia|1819 ship|2}}{{'}}s first voyage, during which she became the first American vessel known to reach the [[South Shetland Islands]]. As a skilled and fearless seal hunter, Palmer achieved his first command at the early age of 21. His vessel, a diminutive [[sloop]] named {{ship||Hero|sloop|2}}, was only {{convert|47|ft|m}} in length. Palmer steered southward in ''Hero'' at the beginning of the Antarctic summer of 1820&ndash;1821. Aggressively searching for new [[Pinniped|seal]] [[Rookery|rookeries]] south of [[Cape Horn]], on November 17, 1820, Palmer and his men became the first Americans and the third group of people to discover the [[Antarctic Peninsula]].  Larger ships skippered by [[Fabian Gottlieb von Bellingshausen]] and [[Edward Bransfield]] had reported sighting land earlier in 1820. Along with English sealer [[George Powell (mariner)|George Powell]], Palmer also co-discovered the nearby [[South Orkney Islands]] archipelago.