New data from NASA’s MRO(Mars Reconnaissance Orbiter, a satellite) shows strong evidence that liquid water flows on Mars.
NASA’s research and observations of this Red planet indicates that once a primitive ocean on Mars had more water than Earth’s Arctic ocean. It is also expected that water may still be present on Mars but there was no evidence until recently.
Mysterious darks streaks appear on Mars slopes during Martian summer, and then disappear during winter season. As you can see in the picture, these downhill flows (known as Recurring Slope Lineae RSL) have a correlation with the presence of liquid water. An imaging spectrometer aboard the satellite MRO has recently detected signatures of hydrated salts at multiples locations near these dark streaks (when the dark streaks were relatively wide). The hydrated salts are believed to be perchlorates. Some perchlorates have characteristics that can keep liquids from freezing. Since the dark streaks only form during the summer, higher temperatures most probably drive water to the surface. The source of this water is still a mystery, which can be surface or subsurface ice or something else.
So why are we so excited about the presence of liquid water on Mars? Well, water is a key ingredient for life and it is also believed that once Mars was a warm and wet world that was suitable for life; Mars’ geological evolution was comparable to Earth’s. Understanding the geology of Mars can help us understand Earth’s past and future, and may help answer the age-old question of whether life exists beyond our home planet.
Interested to know more? The new results were published online on September 28 in Nature Geoscience.