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>Something on Earth is always burning! NASA's Earth Observatory tracks wildfires across the world with <a href="http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MOD14A1_M_FIRE" target="_blank">maps available for viewing</a> from 2000-present. Some wildfires can restore <a href="/earth/ecosystems.html&edu=high&dev=1">ecosystems</a> to good health, but many can threaten human populations, posing a natural disaster threat.</p>
<p>Check out the materials about natural disasters in <a href="/earth/natural_hazards/when_nature_strikes.html&edu=high&dev=1">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 sinuous glowing band of <a
  href="/earth/Magnetosphere/aurora.html&edu=high&dev=1">aurora</a> (the Aurora Australis
  or Southern Lights) loops around the <a
  href="/earth/polar/polar_south.html&edu=high&dev=1">southern polar</a>
region in the
  distance as viewed by astronauts onboard the space shuttle on <a
  href="http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/archives/sts-39.html">STS-039</a>. 
  <a
  href="/earth/Magnetosphere/aurora/aurora_colors.html&edu=high&dev=1">Aurora are produced</a>
  when <a
  href="/physical_science/physics/atom_particle/particle_radiation.html&edu=high&dev=1">energetic particles</a>
 entering the Earth's
  atmosphere from space interact with <a
  href="/physical_science/physics/atom_particle/atom.html&edu=high&dev=1">atoms</a> and <a
  href="/earth/geology/molecule.html&edu=high&dev=1">molecules</a> in the atmosphere and
  release energy, emitted as light.<p><small><em>Courtesy of NASA, Astronaut Overmeyer and Dr. Hallinan</em></small></p>Coral animals build reefs in warm, tropical seawater. However, <a href="/earth/changing_planet/ocean_temperatures_intro.html&edu=high&dev=1">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>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>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=high&dev=1">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=high&dev=1">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&edu=high&dev=1">Apollo
17</a> crew
while traveling to the
<a href="/earth/moons_and_rings.html&edu=high&dev=1">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&edu=high&dev=1">Antarctic</a>,
shrouded in the heavy
<a href="/earth/Atmosphere/cloud.html&edu=high&dev=1">cloud</a> cover
in the southern hemisphere.
Arching cloud patterns show the presence of <a href="/earth/Atmosphere/front.html&edu=high&dev=1">weather
fronts</a>.<p><small><em>Image courtesy of NASA/Apollo 17.</em></small></p>

Windows to the Universe Community

News

Opportunities


Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA