In Washington, DC, NASA published a report stating what they originally thought was water on Mars is more likely to be just markings in the sand as the planet is too dry for water based on data collected recently. The findings from NASA’s Mars Reconnaissance Orbiter shows the Mars environment is probably too dry for microbes to thrive despite the presence of water in hydrated salts and the dark streaks exist only on slopes steep enough for dry grains to descend the way they do on faces of active dunes.
However, the seasonal dark streaks on Mars remain puzzling. Traits with uncertain explanations include their gradual growth, their seasonal reappearance, their rapid fading when inactive, and the presence of hydrated salts, which have water molecules bound into their crystal structure. The new report describes possible connections between these traits and how the streaks form.