Back in the 1970s, the Viking missions observed, for the first time in history, the slope streaks that occur on Mars from time to time. Now, approximately 50 years later, these mysterious slope streaks on Mars are still puzzling the scientists. Some of them believe that a sort of liquid (water, maybe) is what causes them, while others think that the sand is the culprit.
Fortunately, we’re moving closer to solving this puzzle about Mars thanks to modern technology and the bunch of things we’ve learned about the Red Planet since the 70s. A team of scientists from Sweden decided to look into this problem more in-depth and to compare the slope streaks on Mars with a similar phenomenon that takes place on Earth, in Bolivia.
The new study, titled “Are Slope Streaks Indicative of Global-Scale Aqueous Processes on Contemporary Mars?”, issued in the Reviews of Geophysics publication, concluded that so-called “wet” mechanisms are behind the mysterious slope streaks on Mars.
Mysterious Slope Streaks on Mars Might Be Caused By Water
“What we know from observations is the following: Slope streaks range from about a few meters to several kilometers long. They usually have a starting point upslope with gradual widening towards the downslope termini, thus indicating the possible involvement of some flow or mass movement,” said the researchers in an interview.
The scientists believe that some “wet” mechanisms cause these slope streaks on Mars. More precisely, groundwater springs, the formation of brines, or the meltdown of surface ice might be the culprits for this phenomenon which appears suddenly and vanishes slowly across decades.
To find out more, the Swedish researchers went to Bolivia where they noticed a site similar to the tropical regions of Mars, and which also presents slope streaks. Here, on Earth, chloride and sulfate salts, within seasonal brine flows, liquify, generating slope streaks similar to those on Mars. That could mean that the same might happen on the Red Planet, but the researchers admitted that further investigation is needed and directing Mars rovers to study the phenomenon might reveal more details.