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We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.
This Galileo image of Prometheus is similar to the original Voyager picture.
Click on image for full size

Io Discoveries with Voyager

When Voyager flew by Jupiter, no one thought that the moon, Io, would have volcanoes. However, there were three brave scientists who predicted that Voyager would find evidence that Io might be hot enough for volcanoes. The prediction was made just two weeks prior to the Voyager encounter with Io.

To everyone's surprise, when Voyager passed by, it actually caught the Prometheus geyser going off.

Later the three scientists who made the prediction were asked why they had taken the risk of making such a prediction, when they could easily have been wrong. They said that was what it meant to be a scientist.

The Galileo mission to Jupiter continues the exploration of the volcanism of Io.

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Our online store includes fun classroom activities for you and your students. Issues of NESTA's quarterly journal, The Earth Scientist are also full of classroom activities on different topics in Earth and space science!

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The rare arrangement of planets Jupiter, Saturn, Uranus, and Neptune in the 1980's made it possible for the Voyager spacecrafts to visit them over a 12 year span instead of the normal 30. They used gravity...more


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Evolution of Callisto

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Very Large Impact Crater

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Surface of Callisto

The surface of Callisto is deeply pockmarked with craters. It looks to be perhaps the most severely cratered body in the solar system. There are also very large craters to be found there. The severity...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