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 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/k=/teacher_resources/min_intro.html">methane</a>, a powerful <a href="/earth/climate/cli_greengas.html&edu=high&dev=1/k=/teacher_resources/min_intro.html">greenhouse gas</a>. Watch the NBC Learn video - <a href="/earth/changing_planet/permafrost_methane_intro.html&edu=high&dev=1/k=/teacher_resources/min_intro.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/k=/teacher_resources/min_intro.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/k=/teacher_resources/min_intro.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/k=/teacher_resources/min_intro.html">electrons</a>, <a href="/physical_science/physics/atom_particle/proton.html&edu=high&dev=1/k=/teacher_resources/min_intro.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/k=/teacher_resources/min_intro.html">magnetic field of the Earth</a>. These belts were <a href="/earth/Magnetosphere/radiation_belts_discovery.html&edu=high&dev=1/k=/teacher_resources/min_intro.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>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/k=/teacher_resources/min_intro.html">crop withering</a>. <a href="/teacher_resources/online_courses/health/events_health.html&edu=high&dev=1/k=/teacher_resources/min_intro.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/k=/teacher_resources/min_intro.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 iconic image of Earth rising above the surface of the <a href="/earth/moons_and_rings.html&edu=high&dev=1/k=/teacher_resources/min_intro.html">Moon</a>, was taken on December 24, 1968 by astronauts on the <a href="/space_missions/apollo8.html&edu=high&dev=1/k=/teacher_resources/min_intro.html">Apollo 8 mission</a>. Apollo 8 was the first <a href="/space_missions/manned.html&edu=high&dev=1/k=/teacher_resources/min_intro.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>A sinuous glowing band of <a href="/earth/Magnetosphere/aurora.html&edu=high&dev=1/k=/teacher_resources/min_intro.html">aurora</a> (the Aurora Australis or Southern Lights) loops around the <a href="/earth/polar/polar_south.html&edu=high&dev=1/k=/teacher_resources/min_intro.html">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=high&dev=1/k=/teacher_resources/min_intro.html">Aurora are produced</a> when <a href="/physical_science/physics/atom_particle/particle_radiation.html&edu=high&dev=1/k=/teacher_resources/min_intro.html">energetic particles</a> entering the Earth's atmosphere from space interact with <a href="/physical_science/physics/atom_particle/atom.html&edu=high&dev=1/k=/teacher_resources/min_intro.html">atoms</a> and <a href="/earth/geology/molecule.html&edu=high&dev=1/k=/teacher_resources/min_intro.html">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>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=high&dev=1/k=/teacher_resources/min_intro.html">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=high&dev=1/k=/teacher_resources/min_intro.html">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>

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 Earth is the largest and densest rocky planet in the solar system?

Did you know that greenhouse gases are increasing rapidly in the Earth's atmosphere?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Tallus slope
xTallus slope : An accumulation of broken rock fragments at the base of crags or mountain cliffs

Click on the word to find out!

Research Highlights

More than One: Long-Reining Microbe Controlling Ocean Nitrogen Shares the Throne

Marine scientists long believed that a microbe called Trichodesmium, a member of a group called the cyanobacteria, reigned over the ocean's nitrogen budget. New research results reported on-line today...Read more


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