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/moons/games_space_sense.html">earthquake</a> off of Honshu, Japan on <a href="/headline_universe/march112011earthquaketsunami.html&dev=1/moons/games_space_sense.html">11 March 2011</a> generated a <a href="/earth/tsunami1.html&dev=1/moons/games_space_sense.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>An artist's rendering of the moment of impact of a massive <a
  href="/our_solar_system/meteors/meteors.html&dev=1/moons/games_space_sense.html">meteorite</a>
  at the end of the Cretaceous (at the end of the <a
  href="/earth/geology/hist_mesozoic.html&dev=1/moons/games_space_sense.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/moons/games_space_sense.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/moons/games_space_sense.html">massive
  volcanic eruptions</a> may be been responsible for the extinction.<p><small><em>Courtesy of Don Davis, NASA</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&dev=1/moons/games_space_sense.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&dev=1/moons/games_space_sense.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 view of the Earth as seen by the <a href="/space_missions/apollo17.html&dev=1/moons/games_space_sense.html">Apollo
17</a> crew
while traveling to the
<a href="/earth/moons_and_rings.html&dev=1/moons/games_space_sense.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/moons/games_space_sense.html">Antarctic</a>,
shrouded in the heavy
<a href="/earth/Atmosphere/cloud.html&dev=1/moons/games_space_sense.html">cloud</a> cover
in the southern hemisphere.
Arching cloud patterns show the presence of <a href="/earth/Atmosphere/front.html&dev=1/moons/games_space_sense.html">weather
fronts</a>.<p><small><em>Image courtesy of NASA/Apollo 17.</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/moons/games_space_sense.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>This iconic image of Earth rising above the surface of the <a
  href="/earth/moons_and_rings.html&dev=1/moons/games_space_sense.html">Moon</a>,
  was taken on December 24, 1968 by astronauts on the <a
  href="/space_missions/apollo8.html&dev=1/moons/games_space_sense.html">Apollo 8
  mission</a>. Apollo 8 was the first <a
  href="/space_missions/manned.html&dev=1/moons/games_space_sense.html">manned
  mission</a> to the Moon, and entered into lunar orbit on Christmas Eve. That
  evening, the astronauts held a live broadcast from lunar orbit, in which they showed pictures of the Earth and moon as seen from their
  spacecraft.<p><small><em> Image courtesy of   NASA</em></small></p>

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