Earth, our home planet, is a world unlike any other. The third planet from the sun, Earth is the only place in the known universe confirmed to host life. With a radius of 3,959 miles, Earth is the ...

"An epic exploration of possibilities. What If is a Webby Award-winning science web series that takes you on a journey through hypothetical worlds and possibilities, some in distant corners of the ...

The Hidden Demand for Rare Earth Elements Rare earth elements (REEs) might sound like something out of a sci-fi novel, but ...

Prehistoric time line, geologic time scale, photos, facts, maps, and more from National Geographic. Humans have walked the Earth for 190,000 years, a mere blip in Earth's 4.5-billion-year history.