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Young Voices for the Planet DVD in our online store includes 8 films where students speak out and take action on climate change.

Earth's Interior and Surface

Earth, the largest and densest rocky planet, was formed about 4.5 billion years ago. The Earth's interior is divided into four layers, which is typical of rocky planets. Each layer has different characteristics and is made of different elements and minerals.

There are many different types of features on Earth’s surface due to the complexity of our planet. The surface is unique from the other planets because it is the only one which has liquid water in such large quantities. Water forms some features of Earth's surface such as rivers, oceans, beaches and lakes. Other surface features, such as mountains, earthquakes and volcanoes, are formed when large pieces of the Earth’s outer layer move slowly by plate tectonics.

Rainforest vegetation on the Caribbean island of Dominica.  <a href="/earth/rainforest.html&dev=1">Tropical
  rainforests</a> are home to thousands of species of animals, plants, fungi and
  microbes. Scientists suspect that there are many species living in
  rainforests have not yet been found or described. Rainforests get their name
  because they receive a lot of rain - an average of 80 inches (203 cm) a year!<p><small><em>     NBII Digital Image Library - Randolph Femmer, photographer</em></small></p>Gold or Fool’s Gold? There are two easy ways to tell Fool’s Gold, the
  <a
  href="/earth/geology/min_intro.html&dev=1">mineral</a>
  <a
  href="/earth/geology/min_pyrite.html&dev=1">pyrite</a>,
  from real gold. First, pyrite leaves a black streak on a white tile whereas
  gold leaves, well, a gold streak. Also, pyrite is much harder than gold.
  Pyrite is made up of the <a
  href="/earth/geology/periodic_table.html&dev=1">elements</a>
  iron (Fe) and sulfur (S).  Both of these two elements are among the <a
  href="/earth/geology/crust_elements.html&dev=1">eight
  most abundant</a> in the <a
  href="/earth/interior/earths_crust.html&dev=1">Earth’s
  crust</a>.<p><small><em> Courtesy of Corel</em></small></p>This is the Barringer Meteor Crater in Arizona. The diameter is 1.2
  kilomters, and it is 49,000 years old. Compared with other planets, <a
  href="/earth/Interior_Structure/crater.html&dev=1">impact
  craters</a> are rare <a
  href="/earth/Interior_Structure/surface_features.html&dev=1">surface
  features</a> on Earth. There are two main reasons for the low number of
  craters. One is that our <a
  href="/earth/Atmosphere/overview.html&dev=1">atmosphere</a>
  burns up most <a
  href="/our_solar_system/meteors/meteors.html&dev=1">meteoroids</a>
  before they reach the surface. The other reason is that Earth's surface is <a
  href="/earth/interior/plate_tectonics.html&dev=1">continually
  active</a> and erases the marks of craters over time.<p><small><em>D. Roddy and LPI</em></small></p>The most majestic of the volcanoes are composite volcanoes, also
  known as strato-volcanoes. Unlike the <a
  href="/earth/interior/shield_volcanos.html&dev=1">shield
  volcanoes</a> which are flat and broad, composite volcanoes are tall,
  symmetrically shaped, with steep sides, sometimes rising 10,000 feet high.
  They are built of alternating layers of <a
  href="/earth/interior/lava.html&dev=1">lava</a>
  flows, volcanic <a
  href="/earth/interior/ash.html&dev=1">ash</a>,
  cinders, blocks, and bombs.  This is a photo of Mt. Cotopaxi in Ecuador.<p><small><em>The U.S. Geological Survey</em></small></p>Sinkholes are <a href="/teacher_resources/main/frameworks/esl_bi8.html&dev=1">natural hazards</a> in many places around the world. They are formed when water dissolves underlying <a href="/earth/Water/carbonates.html&dev=1">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>Hydrothermal vents in the deep ocean are located at tectonic <a
  href="/earth/interior/seafloor_spreading.html&dev=1">spreading
  ridges</a>. While most of the water in the deep ocean is close to freezing,
  the water at hydrothermal vents is very hot and laden with chemicals.  In
  this <a
  href="/earth/extreme_environments.html&dev=1">extreme
  environment</a>, certain species of <a
  href="/earth/Life/archaea.html&dev=1">Archaea</a>
  and <a
  href="/earth/Life/classification_eubacteria.html&dev=1">Eubacteria</a>
  thrive, enabling a unique <a
  href="/earth/Water/life_deep.html&dev=1">food
  chain</a> including fish, shrimp, giant tubeworms, mussels, crabs, and clams.<p><small><em> Courtesy of NASA</em></small></p>

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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