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.

Sinkholes are <a href="/teacher_resources/main/frameworks/esl_bi8.html&dev=1/heat_present_10feb09.ppsx">natural hazards</a> in many places around the world. They are formed when water dissolves underlying <a href="/earth/Water/carbonates.html&dev=1/heat_present_10feb09.ppsx">limestone</a>, leading to collapse of the surface. Hydrologic conditions such as a lack of rainfall, lowered water levels, or excessive rainfall can all contribute to sinkhole development. On 2/28/2013, a sinkhole suddenly developed under the house outside of Tampa, Florida, leading to the tragic death of its occupant, Jeff Bush.<p><small><em>Image courtesy of Southwest Florida Water Management District</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/heat_present_10feb09.ppsx">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/heat_present_10feb09.ppsx">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>This iconic image of Earth rising above the surface of the <a href="/earth/moons_and_rings.html&dev=1/heat_present_10feb09.ppsx">Moon</a>, was taken on December 24, 1968 by astronauts on the <a href="/space_missions/apollo8.html&dev=1/heat_present_10feb09.ppsx">Apollo 8 mission</a>. Apollo 8 was the first <a href="/space_missions/manned.html&dev=1/heat_present_10feb09.ppsx">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>This is an artist's conception of the Earth and the inner and outer <a href="/glossary/radiation_belts.html&dev=1/heat_present_10feb09.ppsx">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&dev=1/heat_present_10feb09.ppsx">magnetosphere</a>. The radiation belts of the Earth are made up of <a href="/physical_science/physics/atom_particle/electron.html&dev=1/heat_present_10feb09.ppsx">electrons</a>, <a href="/physical_science/physics/atom_particle/proton.html&dev=1/heat_present_10feb09.ppsx">protons</a> and heavier atomic ions. These particles get trapped in the <a href="/earth/Magnetosphere/earth_magnetic_field.html&dev=1/heat_present_10feb09.ppsx">magnetic field of the Earth</a>. These belts were <a href="/earth/Magnetosphere/radiation_belts_discovery.html&dev=1/heat_present_10feb09.ppsx">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>How did life evolve on <a href="/earth/earth.html&dev=1/heat_present_10feb09.ppsx">Earth</a> during the <a href="/earth/past/Archean.html&dev=1/heat_present_10feb09.ppsx">Archean</a>, when the <a href="/sun/sun.html&dev=1/heat_present_10feb09.ppsx">Sun</a> was about 25% weaker than today? The Earth should have been <a href="/earth/polar/cryosphere_glacier1.html&dev=1/heat_present_10feb09.ppsx">glaciated</a>, if <a href="/earth/climate/earth_greenhouse.html&dev=1/heat_present_10feb09.ppsx">greenhouse</a> gas concentration was the same as today. <a href="http://www.manchester.ac.uk/aboutus/news/display/?id=10798">Researchers</a> studying the <a href="/physical_science/physics/atom_particle/isotope.html&dev=1/heat_present_10feb09.ppsx">isotopic</a> signatures of Earth's early atmosphere in <a href="/earth/geology/rocks_intro.html&dev=1/heat_present_10feb09.ppsx">rocks</a> from Northern Australia have ruled out high levels of <a href="/physical_science/chemistry/nitrogen_molecular.html&dev=1/heat_present_10feb09.ppsx">nitrogen</a> as a possible way to increase warming from <a href="/earth/Atmosphere/overview.html&dev=1/heat_present_10feb09.ppsx">atmospheric</a> <a href="/physical_science/chemistry/carbon_dioxide.html&dev=1/heat_present_10feb09.ppsx">carbon dioxide</a>.<p><small><em>Image courtesy of Manchester University</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&dev=1/heat_present_10feb09.ppsx">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&dev=1/heat_present_10feb09.ppsx">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 the Earth’s lithosphere is broken into giant plates, which occasionally move and can produce earthquakes?

Did you know that a significant portion of sea level rise is due to the expansion of sea water due to increasing temperature?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Shadow zone
xShadow zone : The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves. The shadow zone results from S waves being stopped entirely by the liquid core and P waves being b

Click on the word to find out!

Research Highlights

Scientists Study "Glaciovolcanoes," Mountains of Fire and Ice, in Iceland, British Columbia, U.S.

Glaciovolcanoes, they're called, these rumbling mountains where the orange-red fire of magma meets the frozen blue of glaciers. Iceland's Eyjafjallajökull volcano, which erupted recently, is but one of...Read more


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