Earth

Earth, our home planet, is a beautiful blue and white ball when seen from space. The third planet from the Sun, it is the largest of the inner planets. Earth is the only planet known to support life and to have liquid water at the surface. Earth has a substantial atmosphere and magnetic field, both of which are critical for sustaining life on Earth. Earth is the innermost planet in the solar system with a natural satellite – our Moon. Explore our beautiful home planet – unique in our solar system - through the links in this section.

As temperatures rise and soil moisture decreases, plants are stressed, which can lead to <a href="/earth/climate/crops_withering.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">crop withering</a>. <a href="/teacher_resources/online_courses/health/events_health.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Droughts</a> accompanied by increased temperatures can lead to famine, social and political disruptions. Scientists are helping with early identification of drought that might trigger food shortages. Watch the NBC Learn video - <a href="/earth/changing_planet/withering_crops_intro.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Changing Planet: Withering Crops</a> to find out more.<p><small><em>Image taken by Tomas Castelazo, Creative Commons <a href=&quot;http://creativecommons.org/licenses/by/3.0/deed.en&quot;>Attribution 3.0 Unported</a> license.</em></small></p>This image is a montage of high resolutions photographs of the Earth taken in January 2012 by the Visible/Infrared Imager Radiometer Suite (VIIRS) instrument on the Suomi NPP satellite. The image shows many stunning details of <a href="http://www.windows2universe.org/earth/earth.html">our home planet</a> - <a href="http://solarsystem.nasa.gov/multimedia/gallery/VIIRS_4Jan2012.jpg">particularly at high resolution</a>. The beauty of our planet is obvious from space - our blue <a href="http://www.windows2universe.org/earth/Water/overview.html">waters</a>, our white <a href="http://www.windows2universe.org/earth/Atmosphere/cloud.html">clouds</a>, and the green from <a href="http://www.windows2universe.org/earth/Life/life.html">life</a> abundant at the surface.<p><small><em>Image courtesy of NASA</em></small></p>An artist's rendering of the moment of impact of a massive <a href="/our_solar_system/meteors/meteors.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">meteorite</a> at the end of the Cretaceous (at the end of the <a href="/earth/geology/hist_mesozoic.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Mesozoic Era</a>). Many scientists have concluded for decades that a meteorite four to six kilometers in diameter impacted the Earth at this time, resulting in a <a href="/earth/past/KTextinction.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">mass extinction of dinosaurs</a> and many other life forms. Recent research suggests that perhaps <a href="/headline_universe/olpa/chicxulub.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">massive volcanic eruptions</a> may be been responsible for the extinction.<p><small><em>Courtesy of Don Davis, NASA</em></small></p>As permafrost thaws, the land, atmosphere, water resources, ecosystems, and human communities are affected. Coastal areas and hillsides are vulnerable to erosion by thawing of permafrost. Thawing permafrost also causes a positive feedback to global warming, as carbon trapped within the once-frozen soils is released as <a href="/physical_science/chemistry/methane.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">methane</a>, a powerful <a href="/earth/climate/cli_greengas.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">greenhouse gas</a>. Watch the NBC Learn video - <a href="/earth/changing_planet/permafrost_methane_intro.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">Thawing Permafrost and Methane</a> to find out more.<p><small><em>Image courtesy of the USGS</em></small></p>This is an artist's conception of the Earth and the inner and outer <a href="/glossary/radiation_belts.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">radiation belts</a> that surround it. The Earth's radiation belts are just one part of the system called the <a href="/earth/Magnetosphere/overview.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">magnetosphere</a>. The radiation belts of the Earth are made up of <a href="/physical_science/physics/atom_particle/electron.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">electrons</a>, <a href="/physical_science/physics/atom_particle/proton.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">protons</a> and heavier atomic ions. These particles get trapped in the <a href="/earth/Magnetosphere/earth_magnetic_field.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">magnetic field of the Earth</a>. These belts were <a href="/earth/Magnetosphere/radiation_belts_discovery.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">discovered</a> by James Van Allen in 1958, and so they are known as Van Allen Belts.<p><small><em>Courtesy of Windows to the Universe</em></small></p>Coral animals build reefs in warm, tropical seawater. However, <a href="/earth/changing_planet/ocean_temperatures_intro.html&edu=high&dev=1/earth/Atmosphere/moons/ozone_tropo.html">seawater can be too warm</a> for their liking. If waters get too warm, coral animals lose the algae that live within their little bodies, a process called coral bleaching. Without the algae, corals have less nutrition. Unless cooler temperatures return, allowing algae to return, the coral dies.<p><small><em>Credit: UNC</em></small></p>

Explore Earth

Earth's Interior and Surface

Earth, the largest and densest rocky planet, was formed about 4.5 billion years ago. The Earth's ...Read more

Atmosphere

The atmosphere is a mixture of nitrogen (78%), oxygen (21%), and other gases (1%) that surrounds ...Read more

Magnetosphere

The Earth has a magnetic field with north and south poles. The magnetic field of the Earth ...Read more

Moon

The Earth's one natural satellite, the Moon, is more than one quarter the size of Earth itself ...Read more

Earth's Polar Regions

Do you wonder what Earth's Polar Regions are like? Where do polar bears live? Where do penguins ...Read more

Climate and Global Change

Warm near the equator and cold at the poles, our planet is able to support a variety of living ...Read more

Water (The Hydrosphere)

Water is found in many places on Earth including on the surface of the planet, within rocks ...Read more

Life and Ecology (The Biosphere)

What is life? Why is there life on Earth, but not on any other planets in the solar system ...Read more

Natural Hazards

The United Nations estimated that between 1994-2015, there were 6,873 natural disasters worldwide, ...Read more

More about Earth

Historical Events

Full Earth and Space Science    History Calendar (Members only)

Teacher Opportunities

Full Teacher Events Calendar (Educator Members only)

Did you know?

Did you know that the footprints left on the Moon’s surface by astronauts will last for centuries, because there is no wind on the Moon?

Do you know how photosynthesis works?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Subduction zone
xSubduction zone : Subduction is the process of the oceanic lithosphere colliding with and descending beneath the continental lithosphere.

Click on the word to find out!

Research Highlights

Pollution from Asia Circles Globe at Stratospheric Heights

The economic growth across much of Asia comes with a side effect: pollutants from the region are wafting up to the stratosphere during monsoon season. The new finding, in a study led by scientists at the...Read more


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