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.

Coral animals build reefs in warm, tropical seawater. However, <a href="/earth/changing_planet/ocean_temperatures_intro.html&dev=1">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>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">full phase</a>. Secondly, the <a href="/sun/sun.html&dev=1">Sun</a>, <a href="/earth/earth.html&dev=1">Earth</a> and <a href="/earth/moons_and_rings.html&dev=1">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>How did life evolve on <a href="/earth/earth.html&dev=1">Earth</a> during the <a href="/earth/past/Archean.html&dev=1">Archean</a>, when the <a href="/sun/sun.html&dev=1">Sun</a> was about 25% weaker than today? The Earth should have been <a href="/earth/polar/cryosphere_glacier1.html&dev=1">glaciated</a>, if <a href="/earth/climate/earth_greenhouse.html&dev=1">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">isotopic</a> signatures of Earth's early atmosphere in <a href="/earth/geology/rocks_intro.html&dev=1">rocks</a> from Northern Australia have ruled out high levels of <a href="/physical_science/chemistry/nitrogen_molecular.html&dev=1">nitrogen</a> as a possible way to increase warming from <a href="/earth/Atmosphere/overview.html&dev=1">atmospheric</a> <a href="/physical_science/chemistry/carbon_dioxide.html&dev=1">carbon dioxide</a>.<p><small><em>Image courtesy of Manchester University</em></small></p><p>You don't normally see <a href="/space_weather/space_weather.html&dev=1">space weather</a> forecasted on the evening news, but it does impact life on <a href="/earth/earth.html&dev=1">Earth</a> in many ways. What are the threats posed from all of these natural disasters and how can we work to mitigate those threats beforehand? </p> <p>Check out the materials about natural disasters in <a href="/earth/natural_hazards/when_nature_strikes.html&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>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">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">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>This is an artist's conception of the Earth and the inner and outer <a href="/glossary/radiation_belts.html&dev=1">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">magnetosphere</a>. The radiation belts of the Earth are made up of <a href="/physical_science/physics/atom_particle/electron.html&dev=1">electrons</a>, <a href="/physical_science/physics/atom_particle/proton.html&dev=1">protons</a> and heavier atomic ions. These particles get trapped in the <a href="/earth/Magnetosphere/earth_magnetic_field.html&dev=1">magnetic field of the Earth</a>. These belts were <a href="/earth/Magnetosphere/radiation_belts_discovery.html&dev=1">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>

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 majority of water on Earth is held in the Earth’s ocean?

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Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Ooids
xOoids : Small (< 2 mm), spheroidal, layered sedimentary grains, usually composed of calcium carbonate, but sometimes made up of iron- or phosphate-based minerals.

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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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