Continent Continent A continent is one of several very large landmasses of the world. Generally identified by convention rather than any strict criteria, up to seven regions are commonly regarded as continents. Ordered from largest in area to smallest, they are: Asia, Africa, North America, South America, Antarctica, Europe, and Australia. Geologically, the continents largely correspond to areas of continental crust that are found on the continental plates. However, some areas of continental crust are regions covered with water not usually included in the list of continents. Zealandia is one such area (see submerged continents below). Islands are frequently grouped with
Windows on Earth night cycles, night time lights, and other features that help make the exhibit realistic and interactive. Windows on Earth provides the user a view of Earth from an astronaut's viewpoint, with interactive photorealistic views of Earth as if seen from an altitude of 360 km. The program uses GeoFusion's digital Earth visualization system, which renders accurate views of Earth with terrain, satellite imagery, clouds, and other layers. The system is programmed for user interaction, allowing users to "fly" anywhere they wish to see, and zoom in or out to see details. The system's imagery is derived from Landsat, and features