NASA has finally revealed that it has found strongest evidence yet of briny water on Mars proving speculations correct thereby opening doors to the possibility that there could be life in some form on the Red Planet.
Lujendra Ojha of the Georgia Institute of Technology (Georgia Tech) in Atlanta provided the base for the research that eventually found evidence that there is water on Mars in liquid form. Back in 2010 Ojha had noticed puzzling dark streaks, now known as recurring slope lineae (RSL), on slopes on hills on the Red Planet.
These streaks appeared to ebb and flow over time. The findings suggested that the streaks seem to darken in summer while in winter they fade away. The RSL appeared in several locations on the Red Planet when temperatures are above minus 10 degrees Fahrenheit (minus 23 Celsius), and disappear at colder times.
Using an imaging spectrometer on Mars Reconnaissance Orbiter researchers found fresh evidence of hydrated salts on the slopes and according to them they are the key to the dark features on the slopes. These 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.
Ojha said during the press conference that the presence of the hydrated salts were only detected when the seasonal features were widest suggesting that either the dark streaks themselves or a process that forms them is the source of the hydration.
Whatever the case maybe, Ojha continued, the presence of these hydrated salts means that water plays a vital role in the formation of these streaks.
Scientists involved with the study said that hydrated minerals called perchlorates are the reason behind the spectral signatures and they 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.
This is not the first time that perchlorates have been said to be present on Mars. Previous scientific observations have detected perchlorates 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.
“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.”
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.”
The findings are published in Nature Geoscience.