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 studying
the features of Mars have discovered the largest known
valleys in the solar system. These valleys and gorges lie beneath the surface of the planet, under ash, lava, and dust, and were spotted by a satellite in Mars' orbit that can look beneath the surface using lasers. The name of this satellite is
the Mars Global Surveyor.
These giant channels were apparently formed by large amounts of water flowing through them, as similar structures are formed on Earth, except that to form valleys the size of these the water flow through them would have been 50,000 times that of the Amazon River!
The scientists who completed the study say that Mars probably experienced periods of dramatic heating caused by volcanic activity, and this sharp increase in temperature would have caused floods of an incredible scale. They say that the amount of water flowing through the channels they have discovered would have been enough to fill an ocean three times the size of the Mediterranean Sea in less than two months!
The evidence from this study supports the long-held idea that Mars has vast amounts of frozen water, and that from time to time this water is released by volcanic activity. It also suggests that sometime in the future, Mars may again have oceans, lakes and rivers on its surface.
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