Shop Windows to the Universe

Please help support Windows to the Universe, and our activities to help Earth and space science teachers, with a tax-exempt donation today!
This is a cutaway of the possible interior of an icy moon.
Click on image for full size

Interior of Icy Moons

The diagram to the left shows a cutaway of the possible interior structure of an icy moon. The drawing illustrates what used to be postulated for Jupiter's moon Ganymede.

Icy moons are mostly made of ice, therefore there is probably a small core of some rocky material buried inside, covered with ice.

The diagram shows that there may be an ocean of water beneath the surface crust. If the temperature inside an icy moon is just right, then there might be water inside. Such an environment might prove to be habitable for life. For Jupiter's moon Europa, this scenario may prove to be very important.

The history of an icy moon involves cooling, however. So icy moons which may have had a water layer in the past might be completely frozen now.

Shop Windows to the Universe Science Store!

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!

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Cool It! Game

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

Interior of Ganymede

The picture on this page shows what the inside of Ganymede looks like. Scientists have made this model based on measurements by the Galileo spacecraft. The picture shows a samll core of metal (silver),...more

What Is a Mineral?

Minerals are the building blocks of rocks. There are many different types of minerals. All of them are solid and all are made of atoms of elements. Minerals can grow even though they are not alive. Most...more

Interior of Europa

The diagram to the left shows the possible interior of Europa. The composition of the icy moons is mostly ice, therefore there is probably a small core of rocky material buried inside, covered with ice....more

Amalthea

Amalthea was discovered by E Barnard in 1872. Of the 17 moons it is the 3rd closest to Jupiter. Amalthea is about the size of a county or small state. Amalthea is named after the goat in Greek mythology...more

Callisto

Callisto was first discovered by Galileo in 1610. It is the 2nd largest moon in the solar system, and is larger than the Earth's moon. It is about as big as the distance across the United States. Callisto...more

Evolution of Callisto

Measurements by the Galileo spacecraft have been shown that Callisto is the same inside from the center to the surface. This means that Callisto does not have a core at the center. This means that, unlike...more

Very Large Impact Crater

Many different types of surface are shown in this picture. In the front is a huge crater, which goes for a long way over the surface. This crater could be compared to that of Mimas. They both show that...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