Friday, 15 December, 2017

Water flowing through Mars may just be sand, says study

Mars may not have large amounts of water on its surface after all New study: Streaks on Mars sign of flowing sand, not water
Garry Little | 25 November, 2017, 01:04

Lead author of the study, Colin Dundas, a USGS scientists, said, "We've thought of RSL as possible liquid water flows, but the slopes are more like what we expect for dry sand".

According to NASA, recurring slope lineae or RSL are long, dark streaks that expand on the slopes of Mars during warmer seasons, and retract when the temperature gets colder. The fact that these streaks only show up in places where there are steep slopes help highlight the fact that they're probably made of dry material.

The team found that RSL occur on slopes steeper than 27 degrees, and the flow ends on reaching an "angle of repose" where dry sand accumulates and forms a lump, something which is commonly seen on dunes on Earth.

After analysing over 100 RSL features across 10 sites, USGS scientists posit that the behaviour of the streaks corresponded more with the movement of sand or dust, rather than water flows.

Sand stream found in Martian surface. But a closer look reveals behavior that's unlike flowing water.

Mars water
Mars' dark streaks likely to have been caused by sand, not water

When NASA announced the discovery of larger amounts of liquid water on Mars in 2015, hopes were significantly raised that we could one day soon find evidence of life on Earth's neighbour. He discovered they form on Martian dunes that slope at a particular angle. But a new study led by a Flagstaff geologist says that's not the case. Liquid water on today's Mars may be limited to traces of dissolved moisture from the atmosphere and thin films, which are challenging environments for life as we know it. 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.

Darkening and fading might result from changes in hydration. That's bad news in the hunt for microbes, unfortunately.

Well, although the recent study suggests that RSL might not have any liquid water present on it still this mysterious area is on the target of scientists for any sort of evidence of water on Mars.

The researchers report their findings in the journal Nature Geoscience. JPL, a division of Caltech in Pasadena, California, manages the MRO project for the NASA Science Mission Directorate in Washington.

Recommended

Google tracks location even if setting disabled Google tracks location even if setting disabled Even though the information is encrypted when it is sent back to Google , a third party could still compromise the system. Google said the data was collected to improve notifications and message delivery, and was not stored on Google servers.

Meg Whitman to Step Down as Hewlett Packard Enterprise CEO Meg Whitman to Step Down as Hewlett Packard Enterprise CEO "I have tremendous confidence that they will continue to build a great company that will thrive well into the future". HPE added that its Storage, Networking and Technology Services surged 5%, 21% and 2%, respectively.

Singer, former teen idol David Cassidy dead at 67 Singer, former teen idol David Cassidy dead at 67 Bonaduce tweeted early Wednesday that he had "loved and admired David Cassidy for 48 out of my 58 years". "Oh, they're cute. They get flustered and I get flustered, and it's all kind of fun", Cassidy said of his devotees in 1972, when he was 21.