Secrets of the Earth

Raindrops aren't only formed from condensed water vapor; some result from micrometeorites, and others deliver bacteria from the upper atmosphere.

Tsunamis form in the open ocean before making toward land. Science seeks not only to understand these giant waves but also predict them.

Earthquakes can actually affect Earth's gravity, and the ability of scientists to map gravitational fiels has uncovered mysterious anomalies.

Earth's distance from the sun is just right to sustain life, with neighbors Venus and Mars illustrating the impact of a slight difference in location.

A metallic core at the center of the Earth turns the planet into a magnet, generating a field that protects life on the surface from cosmic radiation.

A visit to the researchers at a Colorado storm lab and an examination of lake-effect snow in northern New York reveal the science of blizzards.