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.

<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/=/earth/climate/cli_greengas.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/=/earth/climate/cli_greengas.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>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/=/earth/climate/cli_greengas.html">earthquake</a> and <a href="/earth/tsunami1.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">tsunami</a> processes. Check out the resources <a href="/teacher_resources/2011_AGU-NESTA_GIFT_Workshop.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">here</a>.<p><small><em>NOAA</em></small></p>An image of Hurricane Sandy taken by the GOES-13 satellite on October 28. This category 1 <a href="/earth/Atmosphere/hurricane/hurricane.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">hurricane</a> was huge, spanning a horizontal distance of about one-third the US continental landmass. The storm came onshore in New Jersey, and gradually moved northeast. The storm disrupted the lives of tens of millions in the eastern US, doing billions of dollars in damage, resulting in over 30 deaths. Visit the National Hurricane Center's webpage on <a href="http://www.nhc.noaa.gov/">Hurricane Sandy</a> for details.<p><small><em>Image courtesy of NASA</em></small></p>Lunar eclipses are special events that only occur when certain conditions are met. First of all, the Moon must be in <a href="/the_universe/uts/moon3.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">full phase</a>. Secondly, the <a href="/sun/sun.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">Sun</a>, <a href="/earth/earth.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">Earth</a> and <a href="/earth/moons_and_rings.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">Moon</a> must be in a perfectly straight line. If both of these are met, then the Earth's shadow can block the Sun's light from hitting the Moon. The reddish glow of the Moon is caused by light from the Earth's limb scattering toward the Moon, which is reflected back to us from the Moon's surface.<p><small><em>Image credit - Doug Murray, Palm Beach Gardens, Florida</em></small></p>This first global map of <a href="http://www.windows2universe.org/earth/Water/ocean.html">ocean</a> surface saltiness, released in September 2012 by the NASA Aquarius mission team, shows the distribution of salt in the first 2 cm of the Earth's ocean. <a href="http://www.windows2universe.org/earth/Water/salinity.html">Salinity</a> variations are one of the main drivers of <a href="http://www.windows2universe.org/earth/Water/circulation1.html">ocean circulation</a>, and are closely connected with the <a href="http://www.windows2universe.org/earth/Water/water_cycle.html">cycling of freshwater</a> around the planet. High salinity is seen in the Mediterranean, Atlantic, and the Arabian Sea.<p><small><em>Image courtesy of NASA/GSFC/JPL-Caltech</em></small></p>This iconic image of Earth rising above the surface of the <a href="/earth/moons_and_rings.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">Moon</a>, was taken on December 24, 1968 by astronauts on the <a href="/space_missions/apollo8.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">Apollo 8 mission</a>. Apollo 8 was the first <a href="/space_missions/manned.html&dev=1/earth/Atmosphere/moons/=/earth/climate/cli_greengas.html">manned mission</a> to the Moon, and entered into lunar orbit on Christmas Eve. That evening, the astronauts held a live broadcast from lunar orbit, in which they showed pictures of the Earth and moon as seen from their spacecraft.<p><small><em> Image courtesy of NASA</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 lights of the aurora come in different colors, depending on the energy of the particles that produce the aurora?

Did you know that most of the Earth's clouds and weather are found in lowest level of the Earth’s atmosphere?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Loess
xLoess : An aeolian sediment formed by the accumulation of wind-blown silt and lesser and variable amounts of sand and clay that are loosely cemented by calcium carbonate. Loess is usually homogeneous, highly porous, and is traversed by vertical capillaries t

Click on the word to find out!

Research Highlights

Silver Tells a Story of Early Earth: Water Here Since Planet's Very Early Days

Tiny variations in the isotopic composition of silver in meteorites and Earth rocks are helping scientists put together a timetable of how our planet was assembled, beginning 4.568 billion years ago. Results...Read more


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