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&dev=1/images/chemistry_troposphere.html">earthquake</a> off of Honshu, Japan on <a href="/headline_universe/march112011earthquaketsunami.html&dev=1/images/chemistry_troposphere.html">11 March 2011</a> generated a <a href="/earth/tsunami1.html&dev=1/images/chemistry_troposphere.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 at the University of Michigan have found that <a href="/earth/polar/cryosphere_permafrost1.html&dev=1/images/chemistry_troposphere.html">permafrost</a> in the <a href="/earth/polar/polar_north.html&dev=1/images/chemistry_troposphere.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/images/chemistry_troposphere.html">climate-warming</a> <a href="/physical_science/chemistry/carbon_dioxide.html&dev=1/images/chemistry_troposphere.html">carbon dioxide</a>, to the <a href="/earth/Atmosphere/overview.html&dev=1/images/chemistry_troposphere.html">atmosphere</a> much faster than previously thought.<p><small><em>George Kling, The University of Michigan</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>This is an artist's conception of the Earth and the inner and outer <a href="/glossary/radiation_belts.html&dev=1/images/chemistry_troposphere.html">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/images/chemistry_troposphere.html">magnetosphere</a>. The radiation belts of the Earth are made up of <a href="/physical_science/physics/atom_particle/electron.html&dev=1/images/chemistry_troposphere.html">electrons</a>, <a href="/physical_science/physics/atom_particle/proton.html&dev=1/images/chemistry_troposphere.html">protons</a> and heavier atomic ions. These particles get trapped in the <a href="/earth/Magnetosphere/earth_magnetic_field.html&dev=1/images/chemistry_troposphere.html">magnetic field of the Earth</a>. These belts were <a href="/earth/Magnetosphere/radiation_belts_discovery.html&dev=1/images/chemistry_troposphere.html">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>Sinkholes are <a href="/teacher_resources/main/frameworks/esl_bi8.html&dev=1/images/chemistry_troposphere.html">natural hazards</a> in many places around the world. They are formed when water dissolves underlying <a href="/earth/Water/carbonates.html&dev=1/images/chemistry_troposphere.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>Greenland's <a href="http://www.windows2universe.org/earth/polar/cryosphere_glacier1.html">ice sheet</a> saw a record <a href="http://www.windows2universe.org/headline_universe/olpa/greenland_10dec07.html">melt</a> in July 2012. Scientists studying this event have found that this melting event was triggered by an influx of unusually warm air and amplified by the presence of a blanket of thin low-level <a href="http://www.windows2universe.org/earth/Atmosphere/cloud.html">clouds</a> which pushed temperatures up above freezing. For more information see the <a href="http://www.news.wisc.edu/21638">press release</a> from the University of Wisconsin Madison.<p><small><em>Image courtesy of University of Wisconsin-Madison</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 upper atmosphere of the Earth overlaps with the Earth's ionosphere?

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?

Salinity
xSalinity : The percent of salt in saltwater

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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