Water, which comprises of two-thirds of the planet earth, is divided into five oceans. The southernmost division of the world ocean that encircles Antarctica (south of 60 degree S latitude) is called Antarctic Ocean. It is the fourth largest ocean after Pacific, Atlantic and Indian Ocean. The Arctic Ocean is the only ocean that is smaller than Antarctic Ocean. The Antarctic Ocean has many names like Southern Ocean, The great Southern Ocean, South Polar Ocean, Austral Ocean etc.
The geography of the Antarctic Ocean is very interesting. Antarctic Ocean was formed when the continents of South America and Antarctica moved apart, that opened up the Drake Passage. This happened 30 million years ago. But this long period still makes Antarctic Ocean the youngest of all the oceans. The Antarctic Ocean is flanked by Pacific, Atlantic and Indian Oceans in the north, unlike other oceans which are surrounded by landmass in the north. This also poses a huge difficulty of distinguishing the oceans. In fact the only reason for considering them as different Oceans is the fact that the water of the Antarctic Ocean is very different. The flow of water causes a current called Antarctic Circumpolar current which circulates the water around it very rapidly.