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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.
Schematic view of the Cherenkov effect
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The Cherenkov Effect

The theory of relativity states that no particle can travel at the speed of light in a vacuum. However, light travels at lower speeds in dense media, like water. A particle traveling in water must have a speed less than the speed of light in a vacuum, but it is possible for it to move faster than the speed of light in water. If the particle is charged, it will emit radiation (light). This process is similar to the sonic boom heard when an airplane exceeds the speed of sound. Neutrino interactions with water can produce such particles. Sensitive light detectors measure this Cherenkov radiation in Neutrino experiments.

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Cool It! is the new card game from the Union of Concerned Scientists that teaches kids about the choices we have when it comes to climate change—and how policy and technology decisions made today will matter. Cool It! is available in our online store.

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Cool It! Game

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Solar Eclipse Webcast from Africa - March 29, 2006

On March 29, 2006 a total solar eclipse was visible from parts of Africa. Scientists from the University of Cape Coast in Ghana webcast live video coverage of this event. Windows to the Universe was a...more

The Big Bang

All of the matter and energy in the Universe was initially confined in a very small region until an enormous explosion occurred, causing the Universe to expand. This expansion continues today. ...more

Neutrinos

The neutrino is an extremely light (and possibly massless) neutral particle. The neutrino belongs to the family of leptons, the particles that interact through the so-called weak force. For this reason...more

The Solar Neutrino Problem

Theories about fusion inside the solar core predict the number of neutrinos that should reach Earth. Experiments on Earth have been set up to detect solar neutrinos in order to test the validity of these...more

Creating Elements up to Iron

When the temperature in the core of a star reaches 100 million degrees Kelvin fusion of Helium into Carbon occurs (three Helium nuclei combine to form a nucleus of Carbon). In the same range of temperature...more

Binding Energy

A plot of the binding energy per nucleon vs. atomic mass shows a peak atomic number 56 (Iron). Elements with atomic mass less then 56 release energy if formed as a result of a fusion reaction. Above this...more

Fusion Experiments

There are several experiments worldwide where the conditions for nuclear fusion reactions have been achieved in a controlled manner. The two main approaches that are being explored are magnetic confinement...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF