EARTH
MEASURING UP
If the Sun were as tall as a typical front door, Earth would be the size of a nickel. THIRD ROCK Earth orbits our Sun, a star. Earth is the third planet from the Sun at a distance of about 93 million miles. AS THE WORLD TURNS A day on Earth is 24 hours. Earth makes a complete orbit around the Sun (a year in Earth time) in about 365.24 days. WE'RE ON IT Earth is a rocky planet with a solid and dynamic surface of mountains, canyons, plains and more. Most of our planet is covered in water. BREATHE EASY Earth's atmosphere is 78 percent nitrogen, 21 percent oxygen and 1 percent other ingredients—the perfect balance to breathe and live. OUR COSMIC COMPANION Earth has one relatively large moon. RINGLESS Earth has no rings. ORBITAL SCIENCE Many orbiting spacecraft study the Earth from above—observing the atmosphere, ocean, glaciers, and much more. |
HOME, SWEET HOME
Earth is the perfect place for life as we know it.
PROTECTIVE SHIELD
Our atmosphere protects us from incoming meteoroids, most of which break up in our atmosphere before they can strike the surface.
Earth is the perfect place for life as we know it.
PROTECTIVE SHIELD
Our atmosphere protects us from incoming meteoroids, most of which break up in our atmosphere before they can strike the surface.