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.

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&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.html�">full phase</a>. Secondly, the <a href="/sun/sun.html&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.html�">Sun</a>, <a href="/earth/earth.html&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.html�">Earth</a> and <a href="/earth/moons_and_rings.html&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.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>As temperatures rise and soil moisture decreases, plants are stressed, which can lead to <a href="/earth/climate/crops_withering.html&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.html�">crop withering</a>. <a href="/teacher_resources/online_courses/health/events_health.html&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.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=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.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>An image of Hurricane Sandy taken by the GOES-13 satellite on October 28. This category 1 <a href="/earth/Atmosphere/hurricane/hurricane.html&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.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><p>The United Nations <a href="http://reliefweb.int/sites/reliefweb.int/files/resources/PAND_report.pdf" target="_blank">estimated</a> that between 1994-2015, there were 6,873 natural disasters worldwide, which affected 218 million people and claimed 1.35 million lives. </p> <p>Check out the materials about natural disasters in <a href="/earth/natural_hazards/when_nature_strikes.html&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.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>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=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.html�">methane</a>, a powerful <a href="/earth/climate/cli_greengas.html&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.html�">greenhouse gas</a>. Watch the NBC Learn video - <a href="/earth/changing_planet/permafrost_methane_intro.html&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.html�">Thawing Permafrost and Methane</a> to find out more.<p><small><em>Image courtesy of the USGS</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&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.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&edu=elem&dev=1/earth/Atmosphere/moons/�/earth/climate/year_wo_summer.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 there are many different names for the full Moon?

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?

Lahar
xLahar : A mudflow or landslide composed of pyroclastic material and water that flows down from a volcano, typically along a river valley. Lahars can be huge, fast, and deadly.

Click on the word to find out!

Research Highlights

Triggers of Volcanic Eruptions in Oregon's Mount Hood Investigated

A new study has found that a mixing of two different types of magma is the key to the historic eruptions of Mount Hood, Oregon's tallest mountain, and that eruptions often happen in a relatively short...Read more


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