Antarctica is Earth's southernmost continent. It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean. At 14,000,000 square kilometres (5,400,000 square miles), it is the fifth-largest continent. For comparison, Antarctica is nearly twice the size of Australia.
Antarctica, on average, is the coldest, driest, and windiest continent, and has the highest average elevation of all the continents. Antarctica is a desert, with annual precipitation of only 200 mm (8 in) along the coast and far less inland. The temperature in Antarctica has reached −89.2 °C (−128.6 °F).
Antarctica is a de facto condominium, governed by parties to the Antarctic Treaty System that have consulting status. Twelve countries signed the Antarctic Treaty in 1959, and thirty-eight have signed it since then. The treaty prohibits military activities and mineral mining, prohibits nuclear explosions and nuclear waste disposal, supports scientific research, and protects the continent's ecozone. Ongoing experiments are conducted by more than 4,000 scientists from many nations.
Antarctica Day is an annual event to build global awareness of this landmark institution, celebrating this milestone of peace in our civilization with hope and inspiration for future generations. Growing from 14 nations during its first year, Antarctica Day 2011 involved participants in 28 countries with activities embraced by diverse governmental and non-governmental organizations facilitating direct involvement of schools, teachers and students. Antarctica Day is an opportunity to demonstrate how diverse nations can work together peacefully, continuously using science as a global language of cooperation for decision making beyond national boundaries.