Earth

Our home planet, the only world known to support life.

The fully lit Earth with Africa, Arabia and the Antarctic ice cap under white clouds.
View of the Earth seen by the Apollo 17 crew traveling toward the moon. Credit: NASA. Source, NASA media guidelines.

Earth is the third planet from the Sun and the only place in the universe where we know life exists. About 71% of its surface is covered by water.

The photograph above was taken on 7 December 1972 by the crew of Apollo 17 on their way to the Moon. It shows Africa, the Arabian Peninsula and the ice of Antarctica, and it became one of the most widely reproduced images in history.

What makes Earth special

  • It orbits at a distance where water can be liquid on the surface.
  • Its atmosphere protects life from harmful radiation and small meteoroids.
  • Its magnetic field shields the planet from the solar wind.
  • Its large Moon stabilises the tilt of its axis, which keeps the climate relatively stable.

Read more about our natural satellite on the page The Moon.