← Atlas of the Solar System
Earth seen from space, with blue oceans and white clouds
Plate IV

Earth

The only known world with stable liquid water on its surface, and an atmosphere rich in free oxygen sustained by life itself. Its moon, unusually large relative to the planet, stabilises the tilt of its axis — and with it, the seasons.

Diameter12,742 km
Average distance from Sun149.6 million km (1 AU)
Local year365.25 days
Moons1