See the Mysterious Photos of Water on Mars

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Recurring slope lineae (RSL) are a type of dark streak seen on Martian slopes and are thought to form from flow of liquid water. This image shows RSL in the Aram Chaos, acquired on Jan. 11, 2015.NASA/JPL/University of Arizona
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This image shows the central peak in Porter Crater, acquired on April 17, 2015.NASA/JPL/University of Arizona
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RSL may be due to active seeps of water. These dark flows are abundant along the steep slopes of ancient bedrock in Coprates Chasma. Acquired on Dec. 31, 2013. NASA/JPL/University of Arizona
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Ravines (or very large gullies) are actively forming on Mars during the coldest times of year, when carbon dioxide frost aids mass wasting. In this image, acquired on March 25, 2015, we see warm-season flows in cold-season ravines.NASA/JPL/University of Arizona
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An image of the southeast rim of Hale crater, acquired on Nov. 13, 2014NASA/JPL/University of Arizona
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This RSL is one of the most active sites known on Mars in the central peaks of Hale Crater, acquired on Feb. 20, 2015. NASA/JPL/University of Arizona
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A RSL in Raga Crate, acquired on Feb. 9, 2015.NASA/JPL/University of Arizona
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A surprise landslump in Melas Chasma, acquired on Jan. 15, 2014.NASA/JPL/University of Arizona
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An image of the southeast rim of Hale crater, acquired on Nov. 13, 2014.NASA/JPL/University of Arizona
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This image was acquired in southern winter over part of Asimov Crater, on March 15, 2014, showing the equator-facing slope of a deep trough inside the crater. NASA/JPL/University of Arizona
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RSL along Coprates Chasma Ridge, acquired on July 7, 2013.NASA/JPL/University of Arizona
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Seasonal flows on Palikir Crater, a warm Martian slopes, that may be caused by the flow of salty water on Mars. Acquired on March 15, 2013NASA/JPL/University of Arizona
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RSL in Juventae Chasma, acquired on Jan. 18, 2013.NASA/JPL/University of Arizona
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This image displays a site along a Coprates Chasma ridge shows RSL on generally north-facing slopes, acquired on Oct. 20, 2012.NASA/JPL/University of Arizona
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Right past the sharp, but warped rim of this ancient impact crater are deposits of winter frost, which show up as blue in enhanced color. Acquired on July 16, 2012.NASA/JPL/University of Arizona
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Slope features seen on a wall in Newton crater acquired on May 30, 2011.NASA/JPL/University of Arizona

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