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.

The massive 9.0 magnitude <a href="/earth/geology/quake_1.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">earthquake</a> off of Honshu, Japan on <a href="/headline_universe/march112011earthquaketsunami.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">11 March 2011</a> generated a <a href="/earth/tsunami1.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">tsunami</a> that exceeded 10 meters on the coast near the epicenter. This image shows model projections for the tsunami wave height in cm which are in good agreement with the observed waves. Our thoughts and prayers are with those who were lost, and their families, as we remember this event.<p><small><em><a href="http://blogs.agu.org/wildwildscience/files/2011/03/680_20110311-TsunamiWaveHeight.jpg">NOAA Tsunami Wave Height Projections image</a></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=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.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=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.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>A new study has found that <a href="/earth/Atmosphere/airpollution_intro.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">pollution</a> from <a href="/earth/Atmosphere/particulates.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">fine particles</a> in the air - mainly the result of burning coal or <a href="/earth/interior/eruptions.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">volcanic eruptions</a> - can shade <a href="/earth/Life/cnidarian.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">corals</a> from sunlight and cool the surrounding water resulting in reduced growth rates. Coral growth rates in the Caribbean were affected by volcanic aerosol emissions in the early 20th century and by aerosol emissions caused by humans in the later 20th century. For more information, see the <a href="http://www.exeter.ac.uk/news/featurednews/title_278202_en.html">press release</a>.<p><small><em>Image courtesy of Toby Hudson (Wikimedia Commons)</em></small></p>This first global map of <a href="http://www.windows2universe.org/earth/Water/ocean.html">ocean</a> surface saltiness, released in September 2012 by the NASA Aquarius mission team, shows the distribution of salt in the first 2 cm of the Earth's ocean. <a href="http://www.windows2universe.org/earth/Water/salinity.html">Salinity</a> variations are one of the main drivers of <a href="http://www.windows2universe.org/earth/Water/circulation1.html">ocean circulation</a>, and are closely connected with the <a href="http://www.windows2universe.org/earth/Water/water_cycle.html">cycling of freshwater</a> around the planet. High salinity is seen in the Mediterranean, Atlantic, and the Arabian Sea.<p><small><em>Image courtesy of NASA/GSFC/JPL-Caltech</em></small></p>Sinkholes are <a href="/teacher_resources/main/frameworks/esl_bi8.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">natural hazards</a> in many places around the world. They are formed when water dissolves underlying <a href="/earth/Water/carbonates.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">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>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/h/neptune/h/neptune/neptune_il.html">full phase</a>. Secondly, the <a href="/sun/sun.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">Sun</a>, <a href="/earth/earth.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.html">Earth</a> and <a href="/earth/moons_and_rings.html&edu=elem&dev=1/earth/Atmosphere/moons/h/neptune/h/neptune/neptune_il.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 the ionosphere makes radio communication possible?

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Umbra
xUmbra : The shadow cast by a celestial body

Click on the word to find out!

Research Highlights

New Findings Indicate Sediment Composition Affected the Strength of Sumatran Earthquake

Sumatra experiences frequent seismic activity because it is located near the boundary of two of Earth's tectonic plates. Earthquakes occur at 'subduction zones,' such as the one west of Indonesia, when...Read more


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