Castor Nunatak is a nunatak

Nunatak

A nunatak is an exposed, often rocky element of a ridge, mountain, or peak not covered with ice or snow within an ice field or glacier. The term is typically used in areas where a permanent ice sheet is present...

 3 miles (5 km) southwest of Oceana Nunatak

Oceana Nunatak

Oceana Nunatak is one of the Seal Nunataks, lying at the northwest corner of Robertson Island, off the east coast of Antarctic Peninsula. Discovered by a Norwegian whaling expedition under C.A. Larsen in December 1893, and named after the Oceana Co. of Hamburg, a sponsor of the expedition....

 in the Seal Nunataks group, off the east coast of the Antarctic Peninsula

Antarctic Peninsula

The Antarctic Peninsula is the northernmost part of the mainland of Antarctica. It extends from a line between Cape Adams and a point on the mainland south of Eklund Islands....

. It was first seen and mapped as an island in December 1893 by a Norwegian Sealing expedition under C.A. Larsen, who named it after the Castor, a ship which combined sealing and exploring activities along the west coast of the Antarctic Peninsula under Captain Morten Pedersen in 1893–94. The feature was determined to be a nunatak in 1902 by the Swedish Antarctic Expedition

Swedish Antarctic Expedition

The Swedish Antarctic Expedition was led by Otto Nordenskjöld and Carl Anton Larsen.-Background:Otto Nordenskjöld, a Swedish geologist and geographer, organized and lead a scientific expedition of the Antarctic Peninsula...

 under Otto Nordenskiöld

Otto Nordenskiöld

Nils Otto Gustaf Nordenskjöld was a Finnish and Swedish geologist, geographer, and polar explorer.-Biography:...

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