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Ready, Set, SCIENCE!, by the National Research Council, focuses on K-8 science classsrooms. Check out the other publications in our online store, as well as classroom materials.

Exploratour - Life in the Solar System

Life on Earth obtains energy in many types of formats. The two main process are photosynthesis and respiration. Photosynthesis is the name of the process by which autotrophs (self-feeders) convert water, carbon dioxide, and solar energy into sugars and oxygen. Oxygen is a waste product of this activity. The photosynthetic activity of early bacteria helped build the oxygen content of Earth's atmosphere so that oxygen-dependent animals, including humans, could live.

The reverse of this process, used by heterotrophs (other-feeders) coverts sugars and oxygen into biological energy. Carbon dioxide and water are produced as waste products.

Respiration, unlike photosynthesis, takes advantage of a natural tendency of oxygen to combine with other molecules. Oxygen is very reactive, and when combining with other substances tends to release large amounts of energy. Thus life forms which employ the process of respiration to run their metabolisms are taking advantage of the most chemically efficient and energetic pathway nature provides to produce bioenergy on Earth.

Certain forms of bacteria can covert energy by breaking down exotic molecules without the benefit of photosnythesis or respiration, however. An example is the coversion of acetate to methane by Archaea. Likewise, life elsewhere in the solar system may rely on energy conversion processes yet to be discovered by human science. One way to search for life is to try and detect the waste products from life's activity. Read more about NASA's current attempts to search for life in the Exploratour on NASA's Exploration for Life at the bottom of this page.

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Learn about Earth and space science, and have fun while doing it! The games section of our online store includes a climate change card game and the Traveling Nitrogen game!

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Traveling Nitrogen Classroom Activity Kit

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

ExploraTour - Looking at the World in a Different Light

Even though the sleeping man is no longer on the bed, you can still see where he was lying down. The heat from his body warmed up the bed sheets which are now radiating infrared light toward your eyes....more

ExploraTour - Looking at the World in a Different Light

All warm objects radiate in the infrared. The warmer the object, the higher the frequency and intensity of the radiation. Very hot objects give off other types of radiation in addition to infrared. Click...more

ExploraTour - Looking at the World in a Different Light

Your eye is a wonderful detector of visible light. Different frequencies of light produce different sensations in the eye which we interpret as colors. Our eyes detect light by using light sensitive components...more

ExploraTour - Looking at the World in a Different Light

Imagine you found a pair of special glasses that not only gave you telescopic vision but gave you the ability to see all forms of radiant energy. The universe in visible light contains all the familiar...more

ExploraTour - Looking at the World in a Different Light

This is a volcano on the island of Miyake in Japan. It has erupted, sending hot lava and ash into the air, a total of ten times. The time after one eruption until the next occurred was about twenty years...more

ExploraTour - Looking at the World in a Different Light

The awesome power of a giant black hole was revealed by looking at this galaxy in three different types of light. The picture that you see is of Centaurus A, a very peculiar galaxy. A galaxy is just a...more

ExploraTour - Looking at the World in a Different Light

This is a plant in Gary, Indiana where power is made. We use power to run things like television sets, radios, lights, and microwave ovens. The picture looks very strange because it was taken in infrared....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