Earth is our home planet, and it's the only place in the universe where we know for certain that life exists. Earth formed over 4.5 billion years ago from a swirling cloud of gas and dust squished ...

The Earth's interior is composed of four layers, three solid and one liquid—not magma but molten metal, nearly as hot as the surface of the sun. The deepest layer is a solid iron ball, about ...

There's a lot we don't know about our home planet and solar system. The post Can You Answer These Basic Questions About Earth ...

Here are some fun facts about Earth as we celebrate this planet we live on for Earth Day. The Earth’s diameter at the equator is 7,926 miles. Sign up for our Newsletters Our atmosphere is made ...