Earth

In this episode of Untold Earth, learn what lessons one of the most active and accessible volcanoes on Earth can teach us about our planet's past, present, and future.

Without this restless geologic process, which triggers destructive earthquakes, Earth would not be habitable.

If you, hypothetically, ignore the molten lava core.

An around-the-world tour for Earth Day.

Taking holiday a moment to appreciate how Earth got its water—and eggnog and mulled wine.

Evidence deep within the planet suggests that remnants of Earth's catastrophic twin might still lie below.

The sea level here is hundreds of feet lower than the rest of the ocean.

A number of factors cause you to be lighter or heavier in different parts of the world.

They often get a bad rap, but bacteria prevent erosion, undergird ecosystems, and make artificial snow.

What's beneath our feet is crucial to life on the planet—don't you dare call it dirt.

NASA's Earth Observatory wants your help finding hidden gems in its vast archives.

It's for science, promise.

High-altitude fossils from the deep, deep past.

Earthquakes are just plain inscrutable.