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September 28, 2015
NASA Confirms Evidence That Liquid Water Flows on Today's Mars
Dark, narrow streaks on Martian slopes such as these at Hale Crater are inferred to be formed by seasonal flow of water on contemporary Mars. The streaks are roughly the length of a football field. Image credit: NASA/JPL-Caltech/Univ. of Arizona › Full image and caption
New findings from NASA's Mars Reconnaissance Orbiter (MRO) 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.
"We found the hydrated salts only when the seasonal features were widest, which suggests that either the dark streaks themselves or a process that forms them is the source of the hydration. In either case, the detection of hydrated salts on these slopes means that water plays a vital role in the formation of these streaks," said Lujendra Ojha of the Georgia Institute of Technology (Georgia Tech) in Atlanta, lead author of a report on these findings published Sept. 28 by Nature Geoscience.
Ojha first noticed these puzzling features as a University of Arizona undergraduate student in 2010, using images from the MRO's High Resolution Imaging Science Experiment (HiRISE). HiRISE observations now have documented RSL at dozens of sites on Mars. The new study pairs HiRISE observations with mineral mapping by MRO's Compact Reconnaissance Imaging Spectrometer for Mars (CRISM).
The spectrometer observations show signatures of hydrated salts at multiple RSL locations, but only when the dark features were relatively wide. When the researchers looked at the same locations and RSL weren't as extensive, they detected no hydrated salt.
Ojha and his co-authors interpret the spectral signatures as caused by hydrated minerals called perchlorates. The hydrated salts most consistent with the chemical signatures are likely a mixture of magnesium perchlorate, magnesium chlorate and sodium perchlorate. Some perchlorates have been shown to keep liquids from freezing even when conditions are as cold as minus 94 degrees Fahrenheit (minus 70 Celsius). On Earth, naturally produced perchlorates are concentrated in deserts, and some types of perchlorates can be used as rocket propellant.
Perchlorates have previously been seen on Mars. NASA's Phoenix lander and Curiosity rover both found them in the planet's soil, and some scientists believe that the Viking missions in the 1970s measured signatures of these salts. However, this study of RSL detected perchlorates, now in hydrated form, in different areas than those explored by the landers. This also is the first time perchlorates have been identified from orbit.
MRO has been examining Mars since 2006 with its six science instruments.
"The ability of MRO to observe for multiple Mars years with a payload able to see the fine detail of these features has enabled findings such as these: first identifying the puzzling seasonal streaks and now making a big step towards explaining what they are," said Rich Zurek, MRO project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California.
For Ojha, the new findings are more proof that the mysterious lines he first saw darkening Martian slopes five years ago are, indeed, present-day water.
"When most people talk about water on Mars, they're usually talking about ancient water or frozen water," he said. "Now we know there's more to the story. This is the first spectral detection that unambiguously supports our liquid water-formation hypotheses for RSL."
The discovery is the latest of many breakthroughs by NASA's Mars missions.
"It took multiple spacecraft over several years to solve this mystery, and now we know there is liquid water on the surface of this cold, desert planet," said Michael Meyer, lead scientist for NASA's Mars Exploration Program at the agency's headquarters in Washington. "It seems that the more we study Mars, the more we learn how life could be supported and where there are resources to support life in the future."
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 Scott Murchie of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland; 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 in Pasadena, California, a division of the California Institute of Technology, 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.
More information about NASA's journey to Mars is available online at:
For more information about the Mars Reconnaissance Orbiter, visit:
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'Mars mystery' solved: Free-flowing water discovered on Red Planet, NASA says
Where there is water, there's likely life.
An enhanced color image sequence of seasonal water flows in Horowitz Crater on Mars. NASA/JPL/University of Arizona
WASHINGTON, Sept. 28 (UPI) -- Water is flowing on the Martian surface! Just as many predicted, the scientific breakthrough that NASA hinted at over the weekend is the discovery of water on the Red Planet.
On Twitter, NASA declared a "major scientific finding had been made" and "Mars mystery solved." Now, that mystery has been revealed.
In a new study, NASA scientists detail what they say is the strongest evidence yet of the presence of water -- flowing salty streaks of water that come and go with the Martian seasons.
Scientists have speculated that streak-like erosion may be caused by seasonal springs, but now researchers say they have direct chemical evidence.
Satellite instruments were able to detect the presence of waterlogged molecules, hydrated salts called perchlorates.
"Something is hydrating these salts, and it appears to be these streaks that come and go with the seasons," Lujendra Ojha, one of the lead scientists responsible for the discovery, said in a press release. "This means the water on Mars is briny, rather than pure. It makes sense because salts lower the freezing point of water. Even if RSL are slightly underground, where it's even colder than the surface temperature, the salts would keep the water in a liquid form and allow it to creep down Martian slopes."
There was plenty of speculation on what exactly would be revealed, but most in the science community believe the announcement detail detail the discovery of free flowing water on Mars -- not the discovery of alien life forms. Though, such a discovery may not be far away.
"Water is essential to life as we know it," the researchers wrote in their new study on the subject, published on Monday in the journal Nature Geoscience. "The presence of liquid water on Mars today has astrobiological, geologic and hydrologic implications and may affect future human exploration."
Enhanced color images of flowing water in the Newton Crater on Mars. Scientists say the water melts as part of a seasonal pattern on the Red Planet. NASA/JPL/University of Arizona
There has been plenty of indirect evidence of water's past presence on Mars, but proof of free-flowing water now changes the discussion about life on Mars, making the presence of living organisms more than likely.
The announcement will also embolden those working to establish some sort of human colony or outpost on the Red Planet.
NASA's big announcement was streamed live on NASA TV.
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By William Harwood CBS News September 28, 2015, 11:40 AM
Researchers using data from a NASA satellite orbiting Mars said Monday they have found clear evidence of intermittent flows of salty water on the red planet, the first "unambiguous" signs of liquid water on the frigid world and a possible indicator of microbe-friendly environments below the surface.
"Mars is not the dry, arid planet we thought of in the past," Jim Green, NASA's director of planetary science, told reporters. "Under certain circumstances, liquid water has been found on Mars."
The apparent flows were first noticed in 2010 by Lujendra Ojha, then an undergraduate at the University of Arizona, studying photographs taken by the Mars Reconnaissance Orbiter. Dark streaks were apparent in the sun-facing walls of steep craters near the equator during the warmer summer months.
The streaks appeared to brighten and darken over the martian year, fading away during the winter and showing back up in warmer weather when the temperature climbed back above minus 10 degrees Fahrenheit. Multiple sites later were identified, in craters, cliff faces and mountainsides.
These dark, narrow, 100 meter-long streaks called recurring slope lineae flowing downhill on Mars are inferred to have been formed by contemporary flowing water. The blue color seen upslope of the dark streaks are thought not to be related to their formation, but instead are from the presence of the mineral pyroxene.
NASA/JPL/University of Arizona
Scientists came up with a variety of explanations for the branching channel-like streaks, arguing they could have been caused by some sort of surface phenomenon involving water, dust slides or other non-liquid phenomena. The water hypothesis appeared to be a stretch given the low pressure of the martian atmosphere and constant, below-freezing temperatures.
But spectroscopic data from the Mars Reconnaissance Orbiter has revealed telltale signatures of hydrated salts, known as perchlorates, around numerous streaks known as "recurring slope lineae," or RSLs.
The hydrated minerals are consistent with magnesium perchlorate, magnesium chlorate and sodium perchlorate. Found on Earth in desert environments, perchlorates have been shown in the laboratory to keep liquids from freezing at temperatures as low as minus 94 degrees Fahrenheit.
On Mars, 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," NASA said in a statement.
Researchers said a sub-surface flow of briny water could allow enough liquid to "wick" its way to the surface to explain the recurring slope lineae. Another mechanism could be the absorption of water vapor from the thin martian atmosphere by the perchlorates, which then would dissolve away leaving a water solution behind.
"Regardless, the presence of hydrated salts in these flows means that these features are formed contemporary with liquid water," said Ojha, now studying for his doctorate at the Georgia Institute of Technology and lead author of a paper published Monday by Nature Geoscience.
Dark streaks seen on the sun-facing walls of craters and cliffs near the martian equator are now believed to be the result of rapid, seasonal flows of briny water based on spectroscopic data indicating the presence of hydrated salts that could keep liquids from immediately freezing.
How much water? Alfred McEwen, the principal investigator for the High Resolution Imaging Science Experiment -- HiRISE -- aboard the Mars Reconnaissance Orbiter, said calculations based on the observed streaks indicate the global presence of more than 25 million gallons of liquid water.
That "sounds like a lot if it's all in one place, but that's dispersed over very wide areas," he said. "So what we're dealing with is thin layers of wet soil, not standing water."
Data from a variety of spacecraft have shown that Mars once hosted a warmer, wetter environment with a thicker atmosphere, flowing rivers and large bodies of water on the surface.
While Mars was once habitable for life as it's known on Earth -- water, organic compounds and energy from sunlight were present -- it's not clear how long those conditions persisted or whether life ever had a chance to evolve. Mars today appears to be a cold, desert world.
But the discovery that liquid water still flows on the red planet, even intermittently, bolsters the odds that microbial life of some sort could, in theory, still exist on Mars.
"Water is an essential ingredient for life," said Mary Beth Wilhelm, a researcher at NASA's Ames Research Center and the Georgia Institute of Technology. "Our results may point to more habitable conditions on the near surface of Mars than previously thought."
Another view of "recurring slope lineae," or RSLs, flowing out of a mountainside on Mars.
But she added that it's far from clear whether Earth-like microbes could exist in the martian environment.
"To assess habitablity, we would first need to determine how cold and how concentrated the brine is," she said.
But senior NASA managers were less circumspect.
"Everywhere we go where there's liquid water, whether its deep in the Earth or in the arid regins, we find life," Green said. "We haven't been able to answer the question 'does life exist beyond Earth?' But following the water is a critical element of that. We now have great opportunities to be in the right locations on Mars to thoroughly investigate that."
McEwen said the discovery only strengthened his view that the probability of life on Mars is high.
"There's certainly water somewhere in the crust of Mars, and Mars has received meteorites from Earth, it's been contaminated by Earth," he said. "We know that microbes can survive that trip. So it's very likely, I think, there is life somewhere in the crust of Mars, microbes. But where is it? How accessible is it? Now, maybe, there's something we can find close to the surface. That's what's exciting."
© 2015 CBS Interactive Inc. All Rights Reserved.
NASA Discovers Salty Liquid Water Flows Intermittently on Mars Today, Bolstering Chance for Life
by Ken Kremer on September 28, 2015
These dark, narrow, 100 meter-long streaks called recurring slope lineae flowing downhill on Mars are inferred to have been formed by contemporary flowing water. Recently, planetary scientists detected hydrated salts on these slopes at Hale crater, corroborating their original hypothesis that the streaks are indeed formed by liquid water. The blue color seen upslope of the dark streaks are thought not to be related to their formation, but instead are from the presence of the mineral pyroxene. The image is produced by draping an orthorectified (Infrared-Red-Blue/Green(IRB)) false color image (ESP_030570_1440) on a Digital Terrain Model (DTM) of the same site produced by High Resolution Imaging Science Experiment (University of Arizona). Vertical exaggeration is 1.5. Credits: NASA/JPL/University of Arizona
Story/images updated
NASA and Mars planetary scientists announced today (Sept. 28) that salty “liquid water flows intermittently” across multiple spots on the surface of today’s Mars – trumpeting a major scientific discovery with far reaching implications regarding the search for life beyond Earth and bolstering the chances for the possible existence of present day Martian microbes.
Utilizing spectroscopic measurements and imaging gathered by NASA’s Mars Reconnaissance Orbiter (MRO), researchers found the first strong evidence confirming that briny water flows on the Red Planet today along dark streaks moving downhill on crater slopes and mountain sides.
“Mars is not the dry, arid planet that we thought of in the past. Today we announce that under certain circumstances, liquid water has been found on Mars,” said Jim Green, NASA Planetary Science Director at NASA Headquarters, at a media briefing held today, Sept 28.
“When you look at Earth, water is an essential ingredient. Everywhere we go where there’s liquid water, whether its deep in the Earth or in the arid regions, we find life. This is tremendously exciting.”
“We haven’t been able to answer the question – does life exist beyond Earth? But following the water is a critical element of that. We now have great opportunities to be in the right locations on Mars to thoroughly investigate that,” Green elaborated.
“Water! Strong evidence that liquid water flows on present-day Mars,” NASA officials tweeted about the discovery.
The evidence comes in the form of the detection of mysterious dark streaks, as long as 100 meters, showing signatures of hydrated salt minerals periodically flowing in liquid water down steep slopes on the Red Planet that “appear to ebb and flow over time.”
The source of the water is likely from the shallow subsurface or possibly absorbed from the atmosphere.
Dark narrow streaks called recurring slope lineae emanating out of the walls of Garni crater on Mars. The dark streaks here are up to few hundred meters in length. They are hypothesized to be formed by flow of briny liquid water on Mars. The image is produced by draping an orthorectified (RED) image (ESP_031059_1685) on a Digital Terrain Model (DTM) of the same site produced by High Resolution Imaging Science Experiment (University of Arizona). Vertical exaggeration is 1.5. Credits: NASA/JPL/University of Arizona
Water is a key prerequisite for the formation and evolution of life as we know it. So the new finding significantly bolsters the chances that present day extant life could exist on the Red Planet.
“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.”
“This increases the chance that life could exist on Mars today,” noted Grunsfeld.
The data were gathered by and the conclusions are based on using two scientific instruments – the high resolution imaging spectrometer on MRO known as High Resolution Imaging Science Experiment (HiRISE), as well as MRO’s mineral mapping Compact Reconnaissance Imaging Spectrometer for Mars (CRISM).
The mysterious dark streaks of downhill flows are known as recurring slope lineae (RSL).
They were first detected in 2010 at dozens of sites on the sun facing slopes of deep craters by Lujendra Ojha, then a University of Arizona undergraduate student.
The new finding is highly significant because until today’s announcement, there was no strong evidence that liquid water could actually exist on the Martian surface because the atmospheric pressure was thought to be far too low – its less than one percent of Earth’s.
The flow of water is occasional and not permanent, seasonally variable and dependent on having just the right mix of atmospheric, temperature and surface conditions with salt deposits on Mars.
The RSL with flowing water appear in at least three different locations on Mars – including Hale crater, Horowitz crater and Palikir crater – when temperatures are above minus 10 degrees Fahrenheit (minus 23 Celsius). They appear during warm seasons, fade in cooler seasons and disappear during colder times.
Pure surface water ice would simply sublimate and evaporate away as the temperature rises. Mixing in surface salts lowers the melting point of ice, thereby allowing the water to potentially liquefy on Mars surface for a certain period of time rather than sublimating rapidly away.
“These are dark streaks that form in late spring, grow through the summer and then disappear in the fall,” said Michael Meyer lead scientist for the Mars Exploration Program at NASA Headquarters, at the media briefing.
Years of painstaking effort and laboratory work was required to verify and corroborate the finding of flowing liquid water.
“It took multiple spacecraft over several years to solve this mystery, and now we know there is liquid water on the surface of this cold, desert planet,” said Meyer. “It seems that the more we study Mars, the more we learn how life could be supported and where there are resources to support life in the future.”
The dark, narrow streaks flowing downhill on Mars at sites such as this portion of Horowitz Crater are inferred to be formed by seasonal flow of water on modern-day Mars. The streaks are roughly the length of a football field. These dark features on the slopes are called “recurring slope lineae” or RSL. The imaging and topographical information in this processed view come from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter. Credit: NASA/JPL-Caltech/Univ. of Arizona
Along with the media announcement, the researchers published their findings today in a refereed scientific paper in the Sept. 28 issue of Nature Geoscience.
“We found the hydrated salts only when the seasonal features were widest, which suggests that either the dark streaks themselves or a process that forms them is the source of the hydration. In either case, the detection of hydrated salts on these slopes means that water plays a vital role in the formation of these streaks,” said Lujendra Ojha, now at the Georgia Institute of Technology (Georgia Tech) in Atlanta, and lead author of the Sept. 28 publication in Nature Geoscience.
The scientists “interpret the spectral signatures as caused by hydrated minerals called perchlorates.”
Ojha said the chemical signatures from CRISM were most consistent with the detection of mixtures of magnesium perchlorate, magnesium chlorate and sodium perchlorate, based on lab experiments.
“Some perchlorates have been shown to keep liquids from freezing even when conditions are as cold as minus 94 degrees Fahrenheit (minus 70 Celsius).”
Perchlorates have previously been detected in Martian soil by two of NASA’s surface missions – the Phoenix lander and the Curiosity rover. There is also some evidence that NASA’s Viking missions in the 1970s measured signatures of these salts.
On Earth concentration of perchlorates are found in deserts.
This also marks the first time perchlorates have been identified from Mars orbit.
Locations of RSL features on Mars
So NASA astronaut Mark Kelly exclaimed that he was also super excited about the findings, from his perch serving as Commander aboard the International Space Station (ISS), where he is a member of the first ever “1 Year ISS Mission Crew” aimed at learning how the human body will adapt to the long term missions required to send astronauts to Mars and back.
“One reason why NASA’s discovery of liquid water on #Mars is so exciting: we know anywhere there’s water on Earth, there’s some form of life,” Kelly tweeted today from on board the ISS, upon hearing today’s news.
“When most people talk about water on Mars, they’re usually talking about ancient water or frozen water,” Ojha explained.
“Now we know there’s more to the story. This is the first spectral detection that unambiguously supports our liquid water-formation hypotheses for RSL.”
For a nation that explores
September 28th, 2015
The Saline Slopes of Mars: NASA Confirms Evidence for Flowing Liquid Water
False-color image of RSL on slopes in Hale crater. The blue color is thought not to be related to their formation, but instead are from the presence of the mineral pyroxene. The image is produced by draping an orthorectified (Infrared-Red-Blue/Green(IRB)) false color image (ESP_030570_1440) on a Digital Terrain Model (DTM) of the same site produced by High Resolution Imaging Science Experiment (University of Arizona). Vertical exaggeration is 1.5.
Image Credit: NASA/JPL/University of Arizona
In a finding that is sure to fuel the ongoing debate about possible life on Mars, NASA announced today the confirmation that intriguing seasonal dark streaks running down Sun-facing slopes are indeed flows of liquid water. The water is salty (briny), but just the fact that it is current liquid water, albeit transient and in relatively small amounts, is still big news.
The findings, detailed in a new paper just published, come from the Compact Reconnaissance Imaging Spectrometer for Mars on board the Mars Reconnaissance Orbiter spacecraft (MRO). MRO has been examining the Recurring Slope Lineae (RSL) phenomenon on Mars for several years, and now the spacecraft has confirmed the existence of hydrated salts on RSL slopes from four different RSL locations on the planet. These salts would be leftover deposits from briny water which evaporates after being exposed on the surface for short periods of time. Fresh water would quickly sublimate into the atmosphere, since the atmospheric pressure and temperatures are too low for liquid water to normally remain long on the Martian surface.
RSL emanating out of the walls of Garni crater. The streaks are narrow, but up to several hundred meters in length. Image Credit: NASA/JPL/University of Arizona
“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.”
The RSL flows have been a mystery to planetary scientists for years now; they are long, dark, narrow features running down warmer, Sun-facing slopes on hills or in craters in the mid-latitudes and equatorial regions. MRO has observed them appearing repeatedly on an annual basis. After first appearing in times of warmer temperatures, they tend to fade over time as temperatures cool again, appearing like soil which becomes wet and then gradually dries out. Indeed, the leading hypothesis has been that they are temporary flows of briny liquid water, but confirming that has been difficult, until now. The flows are smaller amounts of water wetting the ground, rather than streams per se, but any liquid water seen in Mars’ hostile environment is an exciting discovery. The streaks are typically only a few meters wide, but can be several hundred meters long.
“We found the hydrated salts only when the seasonal features were widest, which suggests that either the dark streaks themselves or a process that forms them is the source of the hydration. In either case, the detection of hydrated salts on these slopes means that water plays a vital role in the formation of these streaks,” said Lujendra Ojha of the Georgia Institute of Technology (Georgia Tech) in Atlanta, lead author of a report on these findings published September 28 by Nature Geoscience.
Water had been the leading hypothesis to explain the RSL, but that couldn’t be proven until the chemical components of the dark streaks could be analyzed. “The salts are hydrated when we observe them,” Ojha noted. “What was missing was the chemical identity – until now,” he added.
“Recurring Slope Lineae (RSL) are seasonal flows on warm Martian slopes initially proposed, but not confirmed, to be caused by briny water seeps. Here we report spectral evidence for hydrated salts on RSL slopes from four different RSL locations from the Compact Reconnaissance Imaging Spectrometer for Mars on board Mars Reconnaissance Orbiter. These results confirm the hypothesis that RSL are due to present-day activity of briny water.”
Perchlorate salts appear to be the primary salts involved with RSL; such salts have been found by other lander and rover missions to be very common on the Martian surface. The hydrated salts most consistent with the chemical signatures seen in RSL are most likely a mixture of magnesium perchlorate, magnesium chlorate, and sodium perchlorate. On Earth, percholrates can keep liquids from freezing even when conditions are as cold as -94 degrees Fahrenheit (-70 Celsius). The observations from MRO are also the first time that perchlorates have been identified from orbit.
RSL on slopes in Horowitz crater. Image Credit: NASA/JPL-Caltech/University of Arizona
“The ability of MRO to observe for multiple Mars years with a payload able to see the fine detail of these features has enabled findings such as these: first identifying the puzzling seasonal streaks and now making a big step towards explaining what they are,” said Rich Zurek, MRO project scientist at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.
The origin of the water, however, is still not well understood. The three leading theories are melting ice, atmospheric deliquescence by hygroscopic salts, and subsurface aquifers. However, all of them have problems. There is thought to not be enough subsurface ice in the equatorial regions to explain RSL in those locations. Atmospheric deliquescence by hygroscopic salts seems unlikely since there is an observed absence of concentrated deliquescent salts on the surface, and it is still unclear how the Martian atmosphere can sufficiently supply water vapor every year to create RSL. Aquifers could discharge to form the RSL, but RSL on the tops of local peaks are difficult to explain this way. It may turn out that there is more than one cause of RSL, in different regions under different conditions.
From the many orbiter, lander, and rover missions it is now known that Mars used to have a lot more liquid water than it does today, with rivers, lakes, and maybe even oceans. Yes, “water on Mars” has been in the news a lot the last few years, but today’s announcement is significant in that it deals with current liquid water, not just water in the remote past.
Possible RSL have also been seen on the slopes of Mount Sharp in Gale crater (in background of this image), the location of the Curiosity rover, but that has not been confirmed yet. It is also not yet known if the rover would be able to reach them. Image Credit: NASA/JPL-Caltech
“When most people talk about water on Mars, they’re usually talking about ancient water or frozen water,” Ojha said. “Now we know there’s more to the story. This is the first spectral detection that unambiguously supports our liquid water-formation hypotheses for RSL.”
“It took multiple spacecraft over several years to solve this mystery, and now we know there is liquid water on the surface of this cold, desert planet,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program at the agency’s headquarters in Washington. “It seems that the more we study Mars, the more we learn how life could be supported and where there are resources to support life in the future.”
Dark streaks seen on the slopes of Mount Sharp in Gale crater may also be RSL it was noted in the press conference, but that has not been confirmed yet, and if they are, it is still unknown whether the Curiosity rover could get close enough to study them.
The finding of course also brings up the possibility of life (likely microbial at best). Does this increase the chances of current life? Perhaps. The water is very briny, so not the kind you would want to drink, but many microbes on Earth are quite happy living in similar briny water. If life ever started on Mars, it could feasibly continue to survive in such conditions. If there are subsurface aquifers, that would be an exciting discovery, since they could potentially be more habitable than just short-lived flows of water on the surface. We just don’t know yet, and answering that next question will require much more study and exploration.
As noted by Mary Beth Wilhelm at NASA’s Ames Research Center in Moffett Field, Calif., and Georgia Tech, the new findings “warrant further astrobiological investigations.”
“The chances of life in the subsurface are very high,” in the opinion of HiRISE Principal Investigator Alfred McEwen of the University of Arizona Lunar and Planetary Laboratory in Tucson, Ariz. Only with further investigation will we know if he is right.
The press conference can be viewed on YouTube and more information about the Mars Reconnaissance Orbiter mission is here.
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Life on Mars? NASA says planet appears to have flowing water
NASA Confirms Liquid Water on Mars
CAPE CANAVERAL, Fla. (AP) — Mars appears to have flowing rivulets of salty water, at least in the summer, scientists reported Monday in a finding that could have major implications for the possibility of life on the red planet.
"It suggests that it would be possible for there to be life today on Mars," NASA's science mission chief, John Grunsfeld, said at a news conference.
Scientists in 2008 confirmed the existence of frozen water on Mars. But instruments aboard NASA's Mars Reconnaissance Orbiter have yielded the strongest evidence yet that salt water in liquid form flows down certain Martian slopes each summer, according to the researchers.
"Mars is not the dry, arid planet that we thought of in the past," said Jim Green, director of planetary science for NASA. "Under certain circumstances, liquid water has been found on Mars."
The rivulets — if that's what they are, since the evidence for their existence is indirect — are about 12 to 15 feet wide and 300 feet or more long, scientists said.
"What we're dealing with is wet soil, thin layers of wet soil, not standing water," said Alfred McEwen of the University of Arizona at Tucson, the principal scientist for the Mars Reconnaissance Orbiter's high-resolution imaging experiment.
Because liquid water is essential to life, the findings could boost the odds of life on Mars. The researchers said in the journal Nature Geoscience that further exploration is warranted to determine whether microscopic life exists on the planet.
McEwen said he, for one, believes the possibility of life on Mars to be "very high," though it would be microbial and somewhere in the Martian crust.
This undated photo provided by NASA and taken by an instrument aboard the agency's Mars Reconnai …
The presence of liquid water could also make life easier for astronauts visiting or living on Mars. Water could be used for drinking and for creating oxygen and rocket fuel. NASA's goal is to send humans there in the 2030s.
The evidence of flowing water consists of dark, narrow streaks on the surface that tend to appear and grow during the warmest Martian months and fade the rest of the year.
Mars is extremely cold even in summer, and the streaks are in places where the temperature has climbed above minus-10 degrees Fahrenheit. But salt can lower the freezing point of water and melt ice.
The source of the water is a mystery. Scientists noted it could be melting ice, an underground aquifer, water vapor from the thin Martian atmosphere, or some combination.
McEwen said that there appears to be a "significant volume" of water, speculating it could fill many Olympic swimming pools, but that it is spread thin over a wide area.
The scientists said these streaks are on steep slopes in rough terrain, making it difficult for rovers or future human explorers to get there. Robotic landers could come close, though, and observe from a distance, McEwen said. The ultimate goal would be to one day bring samples back to Earth for analysis.
Now that scientists know what they're looking for, a better, more methodical search can be carried out, Green said.
Present-day Mars is nothing like ancient Mars. Three billion years ago and more, our most Earthlike neighbor had a huge ocean, but something radical happened. Exactly what remains a mystery.
The Mars Reconnaissance Orbiter has been circling the planet since 2006.
The lead author of the research paper, Lujendra Ojha, is from Georgia Institute of Technology.
For NASA, at least, the timing couldn't be better. This Friday, the NASA-approved movie "The Martian" has its premiere.
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Water flows on Mars, raising possibility that planet could support life: scientists
CAPE CANAVERAL, Fla (Reuters) - Briny water flows during the summer months on Mars, raising the possibility that the planet long thought to be arid could support life today, scientists analyzing data from a NASA spacecraft said on Monday.
Although the source and the chemistry of the water is unknown, the discovery will change scientists' thinking about whether the planet that is most like Earth in the solar system hosts microbial life beneath its radiation-blasted crust.
"It suggests that it would be possible for life to be on Mars today," John Grunsfeld, NASA's associate administrator for science, told reporters, discussing the study published in the journal Nature Geoscience.
"Mars is not the dry, arid planet that we thought of in the past. Under certain circumstances, liquid water has been found on Mars," said Jim Green, the agency's director of planetary science.
But NASA will not be rushing out to search the newly discovered saltwater residue for life just yet.
Dark narrow streaks called recurring slope lineae emanating out of the walls of Garni crater on Mars …
"If I were a microbe on Mars, I would probably not live near one of these (sites). I would want to live further north or south, quite far under the surface and where there's more of a freshwater glacier. We only suspect those places exist and we have some scientific evidence that they do," Grunsfeld said.
The discovery of the water flows was made when scientists developed a new technique to analyze chemical maps of the surface of Mars obtained by NASA's Mars Reconnaissance Orbiter spacecraft.
They found telltale fingerprints of salts that form only in the presence of water in narrow channels cut into cliff walls throughout the planet's equatorial region.
The slopes, first reported in 2011, appear during the warm summer months on Mars, then vanish when the temperatures drop. The chemical fingerprints of hydrated minerals did likewise, the new study showed.
Scientists suspected the streaks, known as recurring slope lineae, or RSL, were cut by flowing water, but previously had been unable to make the measurements.
Portions of the Martian surface shot by NASA's Mars Reconnaissance Orbiter show many channels fr …
"I thought there was no hope," Lujendra Ojha, a graduate student at Georgia Institute of Technology and lead author of the scientific paper, told Reuters.
Mars Reconnaissance Orbiter makes its measurements during the hottest part of the Martian day, so scientists believed any traces of water, or fingerprints from hydrated minerals, would have evaporated.
Also, the chemical-sensing instrument on the orbiting spacecraft cannot home in on details as small as the narrow streaks, which typically are less than 16 feet (5 meters) wide.
But Ojha and colleagues created a computer program that could scrutinize individual pixels. That data was then correlated with high-resolution images of the streaks. Scientists concentrated on the widest streaks and came up with a 100 percent match between their locations and detections of hydrated salts.
The discovery "confirms that water is playing a role in these features," said planetary scientist Alfred McEwen, with the University of Arizona.
A rock outcrop called Link pops out from a Martian surface. REUTERS/NASA/JPL-Caltech/MSSS
FROM WATER TO SUPPORTING LIFE?
Still unknown is whether minerals are absorbing water vapor directly from Mars' thin atmosphere, or if there is a source of melting ice beneath the surface.
Whatever the water's source, the prospect of liquid water, even seasonally, raises the intriguing prospect that Mars, which is presumed to be a cold and dead planet, could support life today.
However, McEwen said much more information about the water's chemistry would be needed before scientists could make that assessment.
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