This image of the Martian surface shows large valleys called Northwestern sloped valleys (NSV's) that were created by cataclysmic flooding in the distant past.
Courtesy of NASA
The Largest Valley System in the Solar System
News story originally written on August 8, 2001
Scientists have found the largest known
valleys in the solar system -- on Mars! These valleys lie under a covering of dust, ash, and lava, but they could still be seen by a satellite that uses lasers to look below the surface of the planet.
These giant valleys were formed as large amounts of water flowed through them, just like the Grand Canyon was formed on Earth. In order to form valleys the size of the ones on Mars, the water flow through them would have been 50,000 times that of the Amazon River!
Sometime in the past when Mars was warmer, there was running water on Mars. Now the water is frozen. But, someday Mars may have oceans and lakes on its surface again.
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