Exploratour - The Surface of Mars

This graph illustrates one way in which the altimeter instrument studies the planet.
Click on image for full size
Image from: NASA/JPL

Altimeter Shows the Difference

The picture to the left shows the measurement of the size of the bluff which separates the southern and northern hemispheres of Mars. The picture shows the surface of Mars from the north pole to the south pole, as if the planet had been cut in half. If you put your finger on the red line, you can trace the change in the height of the Martian surface.

At the left are the lower, northern plains, then the abrupt cliff which separates the northern plains from the highlands of the south, then the highlands at the right. The height of the bluff at any place along the red line can be read in both kilometers and in miles at either side of the picture.

The picture shows that the southern hemisphere is much more elevated than the northern hemisphere. The southern hemisphere is also much older than the northern hemisphere. The different sizes of the two hemispheres is suggestive that Mars has a giant southern continent.


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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