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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.
The interior of Mars as deduced by Mars Pathfinder.
Click on image for full size
Image from: NASA/JPL

The Interior of Mars, from Mars Pathfinder

Many missions have returned data on the shape of Mars, a measurement which contributes to an understanding of a planet's interior structure. These data first showed that Mars had a huge bulge, now called the Tharsis Ridge. Mars Pathfinder took better data on the shape of Mars by passing over the Martian poles instead of the around the middle.

These data suggest that Mars has a large, and solid core, as shown in the figure to the left. (The figure is a rough drawing and is not meant to show the detailed shape of the core). These findings help address questions which remain about Mars, and contribute to the overall results returned by the Mars Pathfinder mission.

Scientists used to think that because the Martian surface contained so much iron, and the Martian magnetic field was weak, that the early history of Mars was not sufficiently warm for Mars to differentiate, and form a large solid iron core, such as that of the Earth. A large molten iron core would generate a strong magnetic field. Thus, iron must have stayed mostly on the outside layers of Mars, making the surface red with rust.

Recently, Mars Global Surveyor returned the first definitive measurement of a Martian magnetic field. Therefore, if the core of Mars is large and composed of iron as the Mars Pathfinder measurement shows, then this theory about the evolution of Mars may not be completely correct.

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Our online store includes issues of NESTA's quarterly journal, The Earth Scientist, full of classroom activities on different topics in Earth and space science, as well as books on science education!

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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