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.

March 2012 marks the first anniversary of the 9.0 magnitude <a href="/earth/geology/quake_1.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">earthquake</a>, <a href="/earth/tsunami1.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">tsunami</a>, and resulting nuclear accident in Japan on <a href="/headline_universe/march112011earthquaketsunami.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">11 March 2011</a>. The tsunami did massive damage, wiping out entire villages and killing ~16,000 people, and leading to one of the most serious nuclear accidents in history. This image shows before and after photos of the area north of Sendai, where 10,000 people were lost.<p><small><em>Photos by <a href="http://www.nytimes.com/interactive/2011/03/13/world/asia/satellite-photos-japan-before-and-after-tsunami.html?hp">GeoEye/EyeQ</a>.</em></small></p>Coral animals build reefs in warm, tropical seawater. However, <a href="/earth/changing_planet/ocean_temperatures_intro.html&dev=1/earth/Atmosphere/moons/privacy_policy.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>An <a href="http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usc000905e.php">8.6 magnitude earthquake</a> struck on 11 April 2012 off of Banda Aceh, Sumatra, Indonesia, followed by a strong aftershock. Earthquake motion was primarily horizontal. A tsunami warning was issued for the Indian Ocean, but was cancelled at 12:36 UTC. A tsunami was observed at 1 meter or less. Find out more about <a href="/earth/geology/quake_1.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">earthquake</a> and <a href="/earth/tsunami1.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">tsunami</a> processes. Check out the resources <a href="/teacher_resources/2011_AGU-NESTA_GIFT_Workshop.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">here</a>.<p><small><em>NOAA</em></small></p>An artist's rendering of the moment of impact of a massive <a href="/our_solar_system/meteors/meteors.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">meteorite</a> at the end of the Cretaceous (at the end of the <a href="/earth/geology/hist_mesozoic.html&dev=1/earth/Atmosphere/moons/privacy_policy.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&dev=1/earth/Atmosphere/moons/privacy_policy.html">mass extinction of dinosaurs</a> and many other life forms. Recent research suggests that perhaps <a href="/headline_universe/olpa/chicxulub.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">massive volcanic eruptions</a> may be been responsible for the extinction.<p><small><em>Courtesy of Don Davis, NASA</em></small></p>A view of the Earth as seen by the <a href="/space_missions/apollo17.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">Apollo 17</a> crew while traveling to the <a href="/earth/moons_and_rings.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">Moon</a> on December 7, 1972. Africa, Madagascar, and the Arabian Peninsula are visible, and you can barely make out the <a href="/earth/polar/antarctica.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">Antarctic</a>, shrouded in the heavy <a href="/earth/Atmosphere/cloud.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">cloud</a> cover in the southern hemisphere. Arching cloud patterns show the presence of <a href="/earth/Atmosphere/front.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">weather fronts</a>.<p><small><em>Image courtesy of NASA/Apollo 17.</em></small></p><p>Something on Earth is always burning! NASA's Earth Observatory tracks wildfires across the world with <a href="http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MOD14A1_M_FIRE" target="_blank">maps available for viewing</a> from 2000-present. Some wildfires can restore <a href="/earth/ecosystems.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">ecosystems</a> to good health, but many can threaten human populations, posing a natural disaster threat.</p> <p>Check out the materials about natural disasters in <a href="/earth/natural_hazards/when_nature_strikes.html&dev=1/earth/Atmosphere/moons/privacy_policy.html">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>

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 scientists have found rock eating bacteria at the bottom of the sea?

Did you know that individuals don’t evolve, but populations do?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Tsunami
xTsunami : A tsunami is a sea wave of local or distant origin that results from large-scale seafloor displacements associated with large earthquakes, major submarine slides, or exploding volcanic islands.

Click on the word to find out!

Research Highlights

A Star Is Born... But How?

Created in the first three minutes after the Big Bang, hydrogen and helium gave rise to all other elements in the universe.  Stars made this possible. Through nuclear fusion, stars generated elements such...Read more


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