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This image shows the grooved terrain of Ganymede.
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NASA

The Grooved Terrain of Ganymede

This image shows an example of the grooved terrain of Ganymede.

The image clearly shows that some things hit Ganymede and made craters after the grooves were made, because the grooves are underneath the craters. This seems to indicate that the grooves were made almost 4 billion years ago, when the period of cratering was just about finished.

A closeup view of these grooves, provided by the Galileo spacecraft, reveals that the ridges are actually many ridges which have been pulled apart as the crust stretched. The spacing between each groove provides information about the underlying crust.


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Grooves of Ganymede

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Light Terrain of Ganymede

This image shows an example of the light terrain of Ganymede. The image shows the contrast between the light terrain and the dark terrain of Ganymede. The light terrain is where the grooves of Ganymede...more

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Very Large Impact Crater

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF