Observations from NASA's Mars Reconnaissance Orbiter have revealed possible flowing water during the warmest months on Mars.
"NASA's Mars Exploration Program keeps bringing us closer to determining whether the Red Planet could harbor life in some form," NASA Administrator Charles Bolden said, "and it reaffirms Mars as an important future destination for human exploration."
Dark, finger-like features appear and extend down some Martian slopes during late spring through summer, fade in winter, and return during the next spring. Repeated observations have tracked the seasonal changes in these recurring features on several steep slopes in the middle latitudes of Mars' southern hemisphere.
"The best explanation for these observations so far is the flow of briny water," said Alfred McEwen of the University of Arizona, Tucson. McEwen is the principal investigator for the orbiter's High Resolution Imaging Science Experiment (HiRISE) and lead author of a report about the recurring flows published in Thursday's edition of the journal Science.
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Sure it *could* be water, but we'd need to send different instrumentation to determine if it is indeed water. I wonder why the claim of 'briny water' - is the rock known to have large amounts of salt? It would be good to know if it is water.
As for humans on Mars ... AAAHAHAHAHAHAHAHAHAHAHAHAHAHA! Human corpses maybe - even for a short trip to Mars (only a few months) making a large enough vehicle with enough supplies is quite a challenge - and that's not even considering a return trip. However, the dangers are no hindrance - there are enough people on the planet who would gladly go knowing they'll never make it back alive.
Because it's too cold for liquid fresh water. If it is liquid water, it must be briny in order to be liquid at those temperatures.
They mention that the darkening is not due to liquid water. What it could be due to is porosity in the particles causing light scattering and then on warming the porosity fills with water. It could even be a phase change of a hydrated salt.
The problem with liquid water isn't so much the temperature as the vapor pressure. Liquid water would evaporate away at the Martian atmospheric pressure. There is vapor pressure depression in pores, so there could be pore water even at low pressure.
Many salts effloresce, that is change into powder on loss of water. A layer of such a salt a few microns thick would scatter more light as a powder than it would as a denser solid. The apparent motion of the âflowsâ could be related to the presence of different mineral species at those regions which are relics of actual flows a long time ago.
That many of the pictures seem to show changes in light scattering in places without access to ground water flows. If that change is due to hydration changes, the water likely comes from the atmosphere.
Magnesium perchlorate is a likely candidate.
http://adsabs.harvard.edu/abs/2010DPS....42.5103G
First scientists are telling us Earth may have once had two moons, now they say Mars may have salt water....next you will be telling us the Earth is older than 6,000 years!!