A sunrise view of Mars
Julie Rehmeyer
Darkened gullies slice down the edge of a crater in one of the first high-resolution images sent by the Mars Reconnaissance Orbiter.
Univ. Arizona, JPL/NASA
The sharp edges of the channels suggest that they are no more than a few million years old. NASA scientists say that the braided gullies look as if sediment-rich streams had carved them, supporting the notion that water once flowed across much of the Red Planet.
"This shows a soaking-wet Mars," says Alfred McEwen of the University of Arizona in Tucson. The orange areas, enhanced for greater contrast, show clay-rich soil, which the scientists say could have formed only in the presence of water. The lightest areas in the picture are covered in carbon dioxide frost, which will burn off during the Martian day.
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Corrections:
This article incorrectly quotes Alfred McEwen of the University of Arizona, saying that a photo of Martian gullies "shows a soaking-wet Mars." He made that remark about another area of the planet. Furthermore, it is that area, rather than the gullies shown, that contains clay-rich soils.
References:
2006. NASA Orbiter reveals new details of Mars, young and old. NASA/Jet Propulsion Laboratory press release. Oct. 16. Available at http://www.jpl.nasa.gov/news/news.cfm?
release=2006-131.
Further Readings:
Rehmeyer, J. 2006. Web special: Clay magic on Mars. Science News Online (Oct. 14). Available at http://www.sciencenews.org/articles/20061014/fob19.asp.
For a high resolution, enlargable version of this image, go to http://www.nasa.gov/mission_pages/
MRO/multimedia/pia01923.html.
For images and information about the Mars Reconnaissance Orbiter, go to http://www.nasa.gov/mro and http://HiRISE.lpl.arizona.edu.
Sources:
Alfred S. McEwen
Lunar and Planetary Lab
University of Arizona
Tucson, AZ 85721
From Science News, Volume 170, No. 17, October 21, 2006, p. 260.
