Recurring Martian Streaks: Flowing Sand, Not Water?

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https://www.jpl.nasa.gov/news/news.php?feature=7005

Source:  By Jet Propulsion Laboratory News

2017-11-20.  . For GSS A Changing Cosmos chapter 7. Excerpt: Fast Facts: › Seasonal dark streaks on Mars have been described as possible signs of flowing water; a new study shows they are a better fit to dry flow processes. › The steepness of more than 150 of these features was assessed with a telescopic camera on a NASA Mars orbiter. › The findings add to evidence that these environments may be too dry for microbes to thrive, despite the presence of water in hydrated salts. › How seasonal warming triggers these streaks is still a puzzle, and water may be involved.... 

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