Mars might be drier than previously thought

The wall of the Newton Crater on Mars. The dark thick lines spread out horizontally in the picture while the Recurring Slope Lineae run downwards. Credit C. Dundas NASA/JPL/USGS Dark features previously proposed as evidence for significant liquid water flowing on Mars have now been identified as granular flows, where sand and dust move rather than liquid water, according to a new study. The new findings, involving scientists at Durham University, the US Geological Survey (USGS), the University of Arizona , and the Planetary Science Institute indicate that present-day Mars may not have a significant volume of liquid water. The water-restricted conditions that exist on Mars would make it difficult for Earth-like life to exist near the surface of the planet. The research is published Steep rocky slopes Scientists analysed narrow, down-slope trending surface features on Mars that are darker than their surroundings, called Recurring Slope Lineae, or RSL. These RSL features grow incrementally, fade when inactive and recur annually during the warmest time of year on Mars.