Fancy yourself a geography buff? Why don't you test your knowledge with this quiz about the rivers, cities and oceans of the world? Quiz master Terry Stein invites you to answer these 20 geography ...

Seen from space, our planet has often been called a "blue marble." It's not, however, just the swirly white clouds that give Earth its marbled appearance. The continents: They are what complete the ...

Researchers have used computer simulations to analyse how plate tectonics have evolved on Earth over the last three billion years. They show that tectonic processes have changed in the course of the ...