Planet Earth from space

Planet Earth from space

Fig. 4.5 . As illustrated in this image of Africa, the Arabian Peninsula, and the Indian Ocean, the Earth's surface consists of continents and oceans. Continents cover a little more than one-quarter of the Earth's surface, while ocean water covers almost three-quarters of the surface. Our home planet has a thin atmosphere with white clouds of water ice, and enough transparency that you can usually look right through it. The Antarctica ice cap gleams white at the bottom. Apollo 17 astronauts took this image in December 1972 as they left the Earth en route to our Moon. (Courtesy of NASA.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University