Earth is the third planet from the Sun and the only known astronomical object that contains life. While large volumes of water can be found throughout the solar system, only Earth maintains liquid surface water. About 71% of the Earth’s surface is ocean, which exceeds the Earth’s polar ice, lakes and rivers.
The remaining 29% of the Earth’s surface is land, consisting of continents and islands. The surface layer of the Earth is made up of several slowly moving tectonic plates that interact to create mountain ranges, volcanoes and earthquakes. Earth’s liquid outer core generates a magnetic field that shapes Earth’s magnetosphere and deflects destructive solar winds.