The Earth as viewed from the Moon during the Apollo 8 mission.
Click on image for full size
Image courtesy of NASA

Earth as a System

The first time people got a glimpse of the whole Earth was December 1968. Apollo 8 astronauts took pictures of the Earth as they traveled to and from the Moon.  In their photographs, the Earth looks like a small blue and white marble in a sea of black space.  Looking at the planet from that far away makes it easy to see that all its parts - the living things, the air, the water, the ice, and the rocks - are connected.  Everything on Earth is in the same boat floating through space - a system.

Since the 1980s, NASA scientists have been studying the Earth as they study other planets - mainly from above with satellites. Based on this way of looking at Earth, they developed the idea of Earth system science.  

"From space we can view the Earth as a whole system, observe the net results of complex interactions, and begin to understand how the planet is changing in response to natural and human influences," NASA explained in a 2003 report.

There are five parts of the Earth system. Each part has its own collection of materials and processes. However, the parts of the Earth system do not operate on their own.  They all interact with other parts in many ways.

  • The atmosphere extends up from the Earth surface for several hundred kilometers. The lowest part is home to clouds and weather.
  • The biosphere is all living things, from single-celled bacteria to plants and animals.
  • The geosphere includes all minerals, rocks, molten rock, sediments, and soils (although there are important living components to soils as well).
  • The hydrosphere includes the ocean, rivers, lakes, streams, groundwater, water vapor, and even puddles.
  • The cryosphere is the frozen part of the Earth system and includes snow, glaciers, and sea ice.

The Sun has a large impact on the Earth and so it is also considered a part of the Earth system. Almost all the energy on Earth comes from the Sun.   The factors outside the planet, like the Sun and solar system, which have an impact on the Earth system, are sometimes called the Exosphere.

Last modified August 16, 2013 by Roberta Johnson.

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

The Cryosphere

Frozen water is found in many different places on Earth. Snow blankets the ground at mid and high latitudes during winter. Sea ice and icebergs float in the chilly waters of polar oceans. Ice shelves fringe...more

The Earth System Is Changing

Earth is a dynamic place. Materials move around the Earth system in many different ways.  Rocks form and reform through the rock cycle. Water flows through the water cycle. Elements move between living...more

Chemistry

Chemistry is the study of matter, energy, and their interactions. Chemists study the composition of substances, their properties, and how they react with each other under varying circumstances. Indeed,...more

Ocean Gyres

A gyre is another name for a swirling vortex. Ocean gyres are large swirling bodies of water that are often on the scale of a whole ocean basin or 1000’s of kilometers across (hundreds to thousands of...more

Earth's Global Climate

Earth's climate is determined by the amount of energy received from the Sun and the amount of energy held in the Earth system - in short, Earth's radiation budget.  The Sun emits an enormous amount of...more

Content for Climate Change Education Courses

Looking for online content that can be used for a climate change education course or module? Pages linked below can be used to support an introductory climate change education for either a unit or a full...more

Albedo

This picture of the Earth surface was taken from high above the planet in the International Space Station. In this view from above, we can see that there are lots of different things that cover the Earth....more

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