Press Release

NASA Confirms Evidence That Liquid Water Flows on Today’s Mars

New findings from NASA’s Mars Reconnaissance Orbiter (MRO) — including data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), built and operated by the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland — provide the strongest evidence yet that liquid water flows intermittently on present-day Mars.

Using an imaging spectrometer on MRO, researchers detected signatures of hydrated minerals on slopes where mysterious streaks are seen on the Red Planet. These darkish streaks appear to ebb and flow over time. They darken and appear to flow down steep slopes during warm seasons, and then fade in cooler seasons. They appear in several locations on Mars when temperatures are above minus 10 degrees Fahrenheit (minus 23 Celsius), and disappear at colder times.

“Our quest on Mars has been to ‘follow the water,’ in our search for life in the universe, and now we have convincing science that validates what we’ve long suspected,” said John Grunsfeld, astronaut and associate administrator of NASA’s Science Mission Directorate in Washington. “This is a significant development, as it appears to confirm that water — albeit briny — is flowing today on the surface of Mars.”

These downhill flows, known as recurring slope lineae (RSL), often have been described as possibly related to liquid water. The new findings of hydrated salts on the slopes point to what that relationship may be to these dark features. The hydrated salts would lower the freezing point of a liquid brine, just as salt on roads here on Earth causes ice and snow to melt more rapidly. Scientists say it’s likely a shallow subsurface flow, with enough water wicking to the surface to explain the darkening.

This animation simulates a fly-around look at one of the places on Mars where dark streaks advance down slopes during warm seasons, possibly involving liquid water. This site is within Hale Crater. The streaks are roughly the length of a football field.

Credit: NASA/JPL/University of Arizona

“Many of our most notable findings have been about the history of Mars’ atmosphere and environment,” said co-author Scott Murchie of APL, principal investigator for CRISM. “Now, we’re able to make insights into the current conditions on Mars. The ability of researchers to call on data from different instruments — whether two on board MRO, or many across spacecraft and rovers — really provides a powerful suite of information that leads to findings such as this.”

There are eight co-authors of the Nature Geoscience paper, including Mary Beth Wilhelm at NASA’s Ames Research Center in Moffett Field, California and Georgia Tech; CRISM Principal Investigator Murchie of APL; and HiRISE Principal Investigator Alfred McEwen of the University of Arizona Lunar and Planetary Laboratory in Tucson, Arizona. Others are at Georgia Tech, the Southwest Research Institute in Boulder, Colorado, and Laboratoire de Planétologie et Géodynamique in Nantes, France.

The agency’s Jet Propulsion Laboratory (JPL) in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA’s Science Mission Directorate, Washington. Lockheed Martin built the orbiter and collaborates with JPL to operate it.

For more information about the Mars Reconnaissance Orbiter, visit http://www.nasa.gov/mro.