I find it so incredible to think that explorers like James Cook went to uncharted areas of the Pacific, making maps as they went along. In our time of maps and GPS in our pockets and cars, those explorers seems braver or crazier than any astronauts.

In 1772, he was commissioned by the Royal Society to go in search of the rumored Terra Australis. This was a hypothetical continent. Terra Australis is Latin for “South Land” and going back to Aristotle there was a theory that it existed.

It appeared on maps between the 15th and 18th centuries. Cook had already circumnavigated New Zealand, and charted the eastern coast of Australia, but that wasn’t what they wanted him to find, despite its name.

The belief was that Terra Australis was farther south. When Cook left Plymouth in July 1772, the plan was to sail around the bottom of the world.

Why was it believed that a Terra Australis existed? No one had spotted it. But there was a theory going back to the 5th century that continents in the Northern Hemisphere should be balanced by land in the Southern.

British explorer Matthew Flinders had already popularized the naming of Australia after Terra Australis, because he surmised that no one was going to find any significant land mass farther south than Australia.

Captain James Cook and his crew on HMS Resolution and Adventure were the first Europeans to sail below the Antarctic Circle on January 17, 1773.  Pack ice stopped them until the weather warmed up in the southern hemisphere’s midsummer. They crossed the Antarctic Circle three times on this voyage, and on the third crossing, almost discovered Antarctica. They were about 150 miles away, but the ice stopped them.

Antarctica was finally sighted in 1820, but the first confirmed sighting of the mainland cannot be accurately attributed to a single person. Three men sighted the ice shelf or the continent within days or months of each other: Fabian Gottlieb von Bellingshausen, a captain in the Russian Imperial Navy; Edward Bransfield, a captain in the Royal Navy; and Nathaniel Palmer, an American sealer out of Stonington, Connecticut.  It was located where hypothetical Terra Australis had been hypothesized to exist.

When all of this Terra Australis was finally explored and mapped, it proved that the Southern Hemisphere has much less land than the Northern. Terra Australis proved to consist of both Antarctica and Australia.