NASA Astronomy Picture of the Day Collection

White Ridges on Mars

What created these white ridges on Mars? The images [ http://photojournal…] showing the white ridges, including some of the highest resolution images ever taken from Martian orbit, were recorded last year by the Mars Reconnaissance Orbiter [ http://en.wikipedia…] (MRO). A current leading hypothesis [ http://www.jpl.nasa…] is that the white ridges formed as water flowed through underground cracks and bleached [ http://en.wikipedia…] and hardened the edges of surrounding rocks. Over millions of years, surface winds eroded the darker rock leaving the raised white ridges. Such water-created light-colored markings are well known here on Earth [ http://antwrp.gsfc.…]. The hypothesis is particularly interesting as underground water could have helped to support microbial life [ http://www.microbew…] on the red world. The above image resolves surface features as small as one meter across in Candor Chasma [ http://antwrp.gsfc.…] region of huge Valles Marineris [ http://antwrp.gsfc.…] on Mars [ http://www.nineplan…].

HiRISE [ http://hirise.lpl.a…], MRO [ http://mars.jpl.nas…], LPL (U. Arizona) [ http://wwwvims.lpl.…], NASA [ http://www.nasa.gov/]

Mars

Arizona

Goddard Space Flight Center (GSFC)

Jet Propulsion Laboratory (JPL)

Earth

Mars

MRO

Mars Reconnaissance Orbiter (MRO)

High Resolution Imaging Science Experiment (HiRISE)

http://antwrp.gsfc.…

SPD-APOD-ap070220