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The Winter 2010 issue of The Earth Scientist includes a variety of educational resources, ranging from astronomy to glaciers. Check out the other publications and classroom materials in our online store.
This drawing illustrates the general composition of icy moons.

The Composition of Icy Moons

Composition is generally determined by detailed measurements of the spectra of an object. Spectral measurements of the surfaces of some of these moons reveal the presence not only of ice but of several different kinds of snow (crushed ice).

The interior composition can be guessed from density

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Traveling Nitrogen Classroom Activity Kit

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What Is a Mineral?

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Voyager

The rare geometric 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...more

The Magnetospheres of Moons

Since it has been determined that the composition of the moons is mostly ice, there is probably not enough magnetic material for these to have a magnetosphere of their own. Nevertheless, because of the...more

Amalthea

Amalthea was discovered by E Barnard in 1872. Of the 17 moons it is the 3rd closest to Jupiter, with a standoff distance of 181,300 km. Amalthea is about the size of a county or small state, and is just...more

Callisto

Callisto was first discovered by Galileo in 1610, making it one of the Galilean Satellites. Of the 60 moons it is the 8th closest to Jupiter, with a standoff distance of 1,070,000 km. It is the 2nd largest...more

Evolution of Callisto

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Very Large Impact Crater

Many examples of the differing types of terrain are shown in this image. In the foreground is a huge impact crater, which extends for almost an entire hemisphere on the surface. This crater may be compared...more

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