The polar regions are the most inhospitable places on the planet. For centuries humankind has tried - and often failed - to reach and study both the Arctic and Antarctic Circles, losing life and limb in the process. So what have we learnt about these frozen wastelands?
The Arctic region includes parts of Canada, Greenland (a territory of Denmark), Russia, the United States, Iceland, Norway, Sweden and Finland, as well as the Arctic Ocean. Located in that massive frozen sea is the North Pole - the very top of the planet.
Earths southernmost point, the Antarctic, is home to the South Pole. It is the fifth largest continent, measuring 14 million square kilometres, approximately 98 per cent of which is covered in ice. It is surrounded by the South Pacific, South Atlantic and Indian Oceans.
Despite extreme temperatures, the harsh Arctic environment is home to a sparse, but varied human population.
An estimated four million natives live within the Arctic Circle; in Alaska, they are known as Iñupiat and Yup'ik Inuit, Alutiq and Athapaskans; in Canada and Greenland, they are Inuit; in Scandinavia the native people are called Saami; while in Russia, Chukchi and Nenets are but two of 16 recognized minorities.
There has never been an indigenous population in Antarctica. Scientists, researchers, geologists and explorers are the only people there at any given time; even though Antarctica is larger than the US, it is populated by only 9,000 people during summer and 5,000 in winter.
The Arctic is a key region for scientific research. Current studies include biological adaptations, climate change, atmospheric phenomena, glaciology, sea ice dynamics and marine ecosystems. By improving our understanding of natural processes in the relatively undisturbed Arctic environment, scientists hope to contribute to knowledge about the planet as a whole.
As there is very little rain in Antarctica, the continents interior is technically the largest desert in the world. In particular, the Antarctic dry valleys, found in Victoria Land, are among the driest places on Earth. Scientists believe no rain has fallen for two million years. Astronauts have visited the dry valleys as preparation for journeys to the similar lunar landscapes.
There are four types of 'North Pole' recognised by science: Magnetic North, the spot on Earth's surface toward which all magnetic compasses point; Geographic North, located directly above Earth's geographic axis; Geomagnetic North, which relates to Earth's magnetic axis; and the Northern Pole of Inaccessibility, which is the northernmost point in the Arctic Ocean, farthest from land on all sides.
Similarly, four types of 'South Pole' have been identified; mirroring the northern counterpart with the Geographic, the Magnetic and the Geomagnetic South Poles. The fourth, however, is the Ceremonial South Pole: an area set aside for photo opportunities at Amundsen-Scott South Pole Station. It is located a few metres from the Geographic South Pole and because the ice cap is moving at approximately ten metres per year, the stake marker is replaced every year on New Year's Day.