Planet Earth Structure

If you’ve ever gone hiking in the Rocky Mountains or Sierras in the western United States , you know that the higher you go, the colder conditions get. The air is thinner and...

Rivers can form from something as small as a mountain spring or they may start from a large

What if a mighty river could begin as nothing more than a small spring bubbling water out of the Earth? That’s just the case of the Danube River, which begins at a spring in the Black Forest of

Climate around the world and even in the United States varies a lot. Places near the equator tend to be hot and humid most of the year. The sun’s...

In February, 1943 there were several earthquakes around Paricutin, Mexico. One day after the

Do you like to hike or climb mountains? The highest mountains in the

Did you know that a human can live for a month without food, but less than one week without water? Every living thing on Earth depends on water for survival. In the

Have you ever explored a cave? Caves are dark and interesting. You might imagine animals or people that have been in the cave before you. But have you ever wondered how a cave is made? Caves are usually made when water runs over soft rock, such as limestone. The acid in the water slowly eats...