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.

Scientists at the University of Michigan have found that <a href="/earth/polar/cryosphere_permafrost1.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">permafrost</a> in the <a href="/earth/polar/polar_north.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">Arctic</a> is extremely sensitive to sunlight. Exposure to sunlight releases carbon gases trapped in the permafrost, including <a href="/earth/climate/earth_greenhouse.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">climate-warming</a> <a href="/physical_science/chemistry/carbon_dioxide.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">carbon dioxide</a>, to the <a href="/earth/Atmosphere/overview.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">atmosphere</a> much faster than previously thought.<p><small><em>George Kling, The University of Michigan</em></small></p><p>You don't normally see <a href="/space_weather/space_weather.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">space weather</a> forecasted on the evening news, but it does impact life on <a href="/earth/earth.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">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/earth/Atmosphere/moons/triton_atmosphere.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 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/triton_atmosphere.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>An artist's rendering of the moment of impact of a massive <a href="/our_solar_system/meteors/meteors.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">meteorite</a> at the end of the Cretaceous (at the end of the <a href="/earth/geology/hist_mesozoic.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">Mesozoic Era</a>). Many scientists have concluded for decades that a meteorite four to six kilometers in diameter impacted the Earth at this time, resulting in a <a href="/earth/past/KTextinction.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">mass extinction of dinosaurs</a> and many other life forms. Recent research suggests that perhaps <a href="/headline_universe/olpa/chicxulub.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">massive volcanic eruptions</a> may be been responsible for the extinction.<p><small><em>Courtesy of Don Davis, NASA</em></small></p>Coral animals build reefs in warm, tropical seawater. However, <a href="/earth/changing_planet/ocean_temperatures_intro.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">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/earth/Atmosphere/moons/triton_atmosphere.html">full phase</a>. Secondly, the <a href="/sun/sun.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">Sun</a>, <a href="/earth/earth.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.html">Earth</a> and <a href="/earth/moons_and_rings.html&dev=1/earth/Atmosphere/moons/triton_atmosphere.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>

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 many different cultures had myths about Earth goddesses and gods?

Did you know that it can get as cold as -70 degrees Celsius in the Arctic tundra during the winter?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Quaternary
xQuaternary : The Quaternary is the geologic time period comprising about the last 1.65 million years.

Click on the word to find out!

Research Highlights

Even in the Desert, Plants Feel the Heat of Global Warming

Global warming is a hot topic, and it's causing concern for scientists studying winter annuals in the Sonoran Desert. While desert winters have become warmer and drier over the years, climate changes have...Read more


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