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.

<p>You don't normally see <a href="/space_weather/space_weather.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.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/h/neptune/neptune_il.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/h/neptune/neptune_il.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>A new study has found that <a href="/earth/Atmosphere/airpollution_intro.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">pollution</a> from <a href="/earth/Atmosphere/particulates.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">fine particles</a> in the air - mainly the result of burning coal or <a href="/earth/interior/eruptions.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">volcanic eruptions</a> - can shade <a href="/earth/Life/cnidarian.html&dev=1/earth/Atmosphere/moons/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>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&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">methane</a>, a powerful <a href="/earth/climate/cli_greengas.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">greenhouse gas</a>.
Watch the NBC Learn video - <a href="/earth/changing_planet/permafrost_methane_intro.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">Thawing Permafrost and Methane</a> to find out more.<p><small><em>Image courtesy of the    USGS</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/earth/Atmosphere/moons/h/neptune/neptune_il.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/earth/Atmosphere/moons/h/neptune/neptune_il.html">magnetosphere</a>. The radiation belts of the Earth are made up of <a
  href="/physical_science/physics/atom_particle/electron.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">electrons</a>,
<a
  href="/physical_science/physics/atom_particle/proton.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">protons</a>
  and heavier atomic ions. These particles get trapped in the <a
  href="/earth/Magnetosphere/earth_magnetic_field.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">magnetic field of the Earth</a>. 
These belts were <a
  href="/earth/Magnetosphere/radiation_belts_discovery.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.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><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&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.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>A view of the Earth as seen by the <a href="/space_missions/apollo17.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">Apollo
17</a> crew
while traveling to the
<a href="/earth/moons_and_rings.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">Moon</a> on
December 7, 1972.  Africa, Madagascar, and the Arabian Peninsula are
visible, and you can barely make out the
<a href="/earth/polar/antarctica.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">Antarctic</a>,
shrouded in the heavy
<a href="/earth/Atmosphere/cloud.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">cloud</a> cover
in the southern hemisphere.
Arching cloud patterns show the presence of <a href="/earth/Atmosphere/front.html&dev=1/earth/Atmosphere/moons/h/neptune/neptune_il.html">weather
fronts</a>.<p><small><em>Image courtesy of NASA/Apollo 17.</em></small></p>

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