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.

Scientists are concerned that melting Arctic sea ice will increase the amount of fresh water in the <a href="/earth/polar/arctic_currents.html&edu=elem&dev=1">Beaufort Gyre</a>, which could spill out into the Atlantic and cause major climate shifts in North America and Western Europe. Watch the <a href="/earth/changing_planet/freshwater_arctic.html&edu=elem&dev=1">Changing Planet: Fresh Water in the Arctic video</a>.<p><small><em> Courtesy of Jack Cook, WHOI (<a href="http://www.whoi.edu">Woods Hole Oceanographic Institute</a>)</em></small></p>A new study has found that <a href="/earth/Atmosphere/airpollution_intro.html&edu=elem&dev=1">pollution</a> from <a href="/earth/Atmosphere/particulates.html&edu=elem&dev=1">fine particles</a> in the air - mainly the result of burning coal or <a href="/earth/interior/eruptions.html&edu=elem&dev=1">volcanic eruptions</a> - can shade <a href="/earth/Life/cnidarian.html&edu=elem&dev=1">corals</a> from sunlight and cool the surrounding water resulting in reduced growth rates. Coral growth rates in the Caribbean were affected by volcanic aerosol emissions in the early 20th century and by aerosol emissions caused by humans in the later 20th century. For more information, see the <a href="http://www.exeter.ac.uk/news/featurednews/title_278202_en.html">press release</a>.<p><small><em>Image courtesy of Toby Hudson (Wikimedia Commons)</em></small></p>A sinuous glowing band of <a href="/earth/Magnetosphere/aurora.html&edu=elem&dev=1">aurora</a> (the Aurora Australis or Southern Lights) loops around the <a href="/earth/polar/polar_south.html&edu=elem&dev=1">southern polar</a> region in the distance as viewed by astronauts onboard the space shuttle on <a href="http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/archives/sts-39.html">STS-039</a>. <a href="/earth/Magnetosphere/aurora/aurora_colors.html&edu=elem&dev=1">Aurora are produced</a> when <a href="/physical_science/physics/atom_particle/particle_radiation.html&edu=elem&dev=1">energetic particles</a> entering the Earth's atmosphere from space interact with <a href="/physical_science/physics/atom_particle/atom.html&edu=elem&dev=1">atoms</a> and <a href="/earth/geology/molecule.html&edu=elem&dev=1">molecules</a> in the atmosphere and release energy, emitted as light.<p><small><em>Courtesy of NASA, Astronaut Overmeyer and Dr. Hallinan</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=elem&dev=1">methane</a>, a powerful <a href="/earth/climate/cli_greengas.html&edu=elem&dev=1">greenhouse gas</a>. Watch the NBC Learn video - <a href="/earth/changing_planet/permafrost_methane_intro.html&edu=elem&dev=1">Thawing Permafrost and Methane</a> to find out more.<p><small><em>Image courtesy of the USGS</em></small></p><p>The United Nations <a href="http://reliefweb.int/sites/reliefweb.int/files/resources/PAND_report.pdf" target="_blank">estimated</a> that between 1994-2015, there were 6,873 natural disasters worldwide, which affected 218 million people and claimed 1.35 million lives. </p> <p>Check out the materials about natural disasters in <a href="/earth/natural_hazards/when_nature_strikes.html&edu=elem&dev=1">NBC Learn Videos</a>, and their earth system science connections built up by the related secondary classroom activities.</p><p><small><em>NBC Learn</em></small></p>As temperatures rise and soil moisture decreases, plants are stressed, which can lead to <a href="/earth/climate/crops_withering.html&edu=elem&dev=1">crop withering</a>. <a href="/teacher_resources/online_courses/health/events_health.html&edu=elem&dev=1">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=elem&dev=1">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>

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 Earth’s magnetic field protects us from radiation from space?

Did you know that the Earth’s magnetic field has reversed its orientation irregularly many times over Earth’s history?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Spreading ridge
xSpreading ridge : An oceanic spreading ridge is the fracture zone along the ocean bottom where molten mantle material comes to the surface, thus creating new crust.

Click on the word to find out!

Research Highlights

Deadly Tonga Earthquake Revealed as Three Big Quakes

A magnitude-8.1 earthquake and tsunami that killed 192 people last year in Samoa, American Samoa and Tonga was in fact a triple-whammy. The 8.1 "great earthquake" concealed and triggered two...Read more


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