 Channels near the Warrego Valles, as seen byTHEMIS. These branched channels are strong evidence for flowingwater on Mars, perhaps during a much warmer period. | |
| Coordinates | 42°12′S93°00′W / 42.2°S 93°W /-42.2; -93 |
|---|---|
TheWarrego Valles are a set of channels in an ancient river valley in theThaumasia quadrangle of Mars, located at 42.2° south latitude and 93° west longitude. They are 188 km long and were named after ariver in Australia.[1]
Mariner 9 andViking Orbiter images showed a network of branching valleys in Thaumasia called the Warrego Valles. These networks are evidence that Mars may have once been warmer, wetter, and perhaps had precipitation in the form of rain or snow. At first glance they resemble river valleys on Earth. But sharper images from more advanced cameras reveal that the valleys are not continuous.[citation needed] They are very old and may have been eroded. A picture below shows some of these branching valleys.[2] A study with theMars Orbiter Laser Altimeter,Thermal Emission Imaging System (THEMIS) and theMars Orbiter Camera (MOC) support the idea that the Warrego Valles were formed from precipitation.[3]
Planetary scans display evidence of rainfall related processes such asfluvial erosion. However, the digitate pattern formed by the system is most consistent withground-water sapping processes. It formed in the southern highlands by tectonic fractures dated to be early Hesperian cross cut and have in turn been cross cut by the valley system. This implies that Warrego Valles was still actively forming well into theHesperian Era.[4]
This article incorporates text from this source, which is in thepublic domain.
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