The salts, which are absent from the surrounding terrain, are thought to have been left by water flowing down the sides of hills or crater rims.
Nasa planetary science director Dr Jim Green said Mars now had to be seen in a new light.
NASA reported Monday that dark, narrow streaks on Mars’ surface that tend to appear and grow during the warmest months on Mars and fade the rest of the year might actually be flowing streams of salty water.
Michael Meyer, lead scientist for the Mars Exploration Program, said scientists haven’t been able to figure out, until now, the “waxing and waning of these dark streaks on the surface”.
“Liquid water is a key requirement for life on Earth”, study lead author Lujendra Ojha, of the Georgia Institute of Technology in Atlanta, told Space.com via email.
There may not be “star trek”-type of extra-terrestrials, but Nasa scientists say we may be close to finding evidence of some form of life on Mars””. “The brine on Mars might not directly support life but it suggests that the arid world isn’t as dry as once thought”. Scientists have theorized that more than 4 billion years ago, the Red Planet had enough water to fill lakes and rivers, though today’s findings show the most direct evidence of the water. “It is a concrete question that we can answer”, said John Grunsfeld, astronaut and associate administrator of NASA’s Science Mission Directorate in Washington.
It is widely accepted that the Red Planet once hosted plentiful water in liquid form, and still has water today, albeit frozen in ice underground. Now scientists will explore further to find out if there is a substantial amount of water in aquifers close to the surface.
Perchlorates are highly absorbent and lower the freezing point of water so that it remains liquid at colder temperatures.
NASA officials say they will launch the insight lander in 2016 to look at the interior of Mars, and in 2020, a new NASA rover will bring Martian samples back to Earth for analysis.
As it turns out, scientists now believe that the mysterious streaks, which disappear and reappear based on the temperature, are likely the result of water being wicked up to the surface from a shallow subsurface flow. 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.
“It’s very exciting. The implications are even more exciting”, said Dr. Mark Hammergren, astronomer, Adler Planetarium. “Under certain circumstances, liquid water has been found on Mars”. “This is a significant development, as it appears to confirm that water-albeit briny -is flowing today on the surface of Mars”.