Rating is available when the video has been rented.
This feature is not available right now. Please try again later.
Published on Apr 28, 2010
Most of the Earth is hot, molten metal and rock. In fact, the inhabitable part makes up less than 1% of the planet's mass. ➡ Subscribe: http://bit.ly/NatGeoSubscribe
About National Geographic: National Geographic is the world's premium destination for science, exploration, and adventure. Through their world-class scientists, photographers, journalists, and filmmakers, Nat Geo gets you closer to the stories that matter and past the edge of what's possible.