Have you ever been extremely hot and extremely thirsty? Go with me in your imagination to South America, to the country of Chile. There is a desert there, the Atacama Desert. In the Atacama Desert it does not rain for centuries at a time. This forsaken, narrow strip of land lies along the western coast of South America. It is protected from clouds by the Andes Mountains, the world''s second highest mountain range.

Some parts of the Atacama Desert have not seen rain in 400 years. Although the desert is located right next to the Pacific Ocean, the prevailing winds come down from the lofty mountains and sweep out to sea.

But as dry as it is, even the Atacama supports life. There are tiny pockets where fog from the sea creates enough moisture for plants and even some animals.

As we open the…