Earth is about eight light minutes away from the Sun and orbits it, taking a year (about 365.25 days) to complete one revolution.
Of the four rocky planets, it is the largest and most massive. It is the densest planet in the Solar System. Severe weather, such as tropical cyclones, thunderstorms, and heatwaves, occurs in most areas and greatly impacts life.Įarth is an ellipsoid with a circumference of about 40,000 km. A region's climate is governed by latitude, but also by elevation and proximity to moderating oceans. Greenhouse gases in the atmosphere like carbon dioxide (CO 2) trap a part of the energy from the Sun close to the surface. Water vapor is widely present in the atmosphere and forms clouds that cover most of the planet. More solar energy is received by tropical regions than polar regions and is redistributed by atmospheric and ocean circulation. Earth's liquid outer core generates the magnetic field that shapes Earth's magnetosphere, deflecting destructive solar winds.Įarth's atmosphere consists mostly of nitrogen and oxygen. Earth's surface layer is formed of several slowly moving tectonic plates, interacting to produce mountain ranges, volcanoes, and earthquakes. The remaining 29% of Earth's surface is land, consisting of continents and islands.
About 71% of Earth's surface is made up of the ocean, dwarfing Earth's polar ice, lakes, and rivers. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. Earth is the third planet from the Sun and the only astronomical object known to harbor life.