Saturday, October 3, 2015

" The Waters of Mars."

Channels cut in the Martian surface as shot by NASA’s
Mars Reconnaissance Orbiter in 2011.
When the News story that (1)>> NASA was supposed to make a big announcement this week , I had a skeptical "ah ha" . I have heard this before . It's OLD NEWS for me , way out late . So is it exciting ?   NASA drummed up the idea that "life" was found on Mars. Leaving us guessing . It was close Yes,  (2)>>MARS HAS WATER on it's surface  ! It's a bit "briny" . How about having  a mixture of Chlorine , and acid . Sorry for my ridicule ,but NASA has known that Mars has water since the 1960's . Whatever what we might call "water" , it's not safe water for human consumption . As for "life" the implications of it might be astounding. That represents a shift in tone for NASA, where officials have repeatedly played down the notion that the dusty and desolate landscape of Mars could be inhabited today.But now, John M. Grunsfeld, NASA’s associate administrator for science, talked of sending a spacecraft in the 2020s to one of these regions, perhaps with experiments to directly look for life.  .FINDING  liquid water anywhere in the solar system is a huge deal, because the evidence for it has been so limited, and life as we know it depends on liquid water. "Follow the water" has been an astrobiological mantra. This may seem slightly narrow-minded, in that one could imagine alien life of a completely different chemical nature, but even the most imaginative thinkers, such as Carl Sagan, were water chauvinists and carbon chauvinists. Of course, this isn’t the first time water has been discovered on Mars. We know that water is laced within Mars regolith; we know there’s water locked in Mars’ ice caps and below the surface; we know that Mars once possessed rivers, lakes and even seas. The last few years of discoveries by our Mars orbiter, lander and rover armada have revolutionized our understanding of Earth’s smaller neighbor. But this time NASA’s Mars Reconnaissance Orbiter has made comprehensive measurements of what appear to be seasonal flows of liquid water on a global scale on modern Mars.Scientists have long known that large amounts of water remain — but frozen solid in the polar ice caps. There have been fleeting hints of recent liquid water, like fresh-looking gullies, but none have proved convincing.

What kind of "water" on Mars Today?
(1)>> I didn't watch the full press conference, but I did the read the paper, and I skipped to the part you said was relevant and was able to see the relevant frame from the video (my connection seems to be shitting out right now).They report absorption lines in Figure 1 at 1.4 microns and 1.9 microns, consistent with the presence of liquid water, but I think they have better spectroscopic evidence of perchlorate salts. These were taken from fourrecurring slope linnae (which were also photographed in the visible spectrum). RSLs are streaks that form on downhill slopes during the Martian summer.Water being found on Mars does not mean that you can just drink the stuff . First of all the Planet Mars has a  (4)>>vary low atmospheric pressure . As an example our Earth mean surface pressure based on barometric readings  as about 1036 MB ( Millibars) , the lowest is on Mt . Everest which has been measure at 29,000 FT as 300 MB . Even at 300 MB water is stable , but boils , since Mt. Everest is at 29,000 FT it's often a vapor or ice . So Lets go to Mars , all most all the scientific probes have  measured  the surface Mars pressures between 6 to 11 MB . It depends on location ,  surface depth . The lowest Martian pressure is on  (3)>> MONS OLYMPUS at 78 ,000 FT and its scarcely 1 MB . So what does this translate to ? First is that 11 MB on Mars is equivalence to being at 100,000 FT on Earth . A human being would need a Oxygen and pressure suit just to survive .  So anything that's a liquid , like human blood and water boil . So what we know today about Mars is that most of the water that exists is mostly frozen , or in a vapor state . We have seen water ice clouds on Mars on a balmy day , Mars has many kinds of clouds . Although Mars is smaller, at 11% of Earth's mass, and 50% farther from the Sun than the Earth, its climate has important similarities, such as the polar ice
This intriguing image was taken by orbital probe HiRISE .Recurring slope lineae (RSL) are narrow (0.5-5 m), relatively dark markings on steep (25°-40°) slopes; repeat MRO/HiRISE images show them to appear and incrementally grow during warm seasons and fade in cold seasons.

capsseasonal changes and the observable presence of weather patterns. It has attracted sustained study from planetologists and climatologists. While Mars's climate has similarities to Earth's, including seasons and periodic ice ages, there are also important differences, such as much lower thermal inertia. Mars' atmosphere has a scale height of approximately 11 km (36,000 ft), 60% greater than that on Earth. Mars' dust storms can kick up fine particles in the atmosphere around which clouds can form. These clouds can form very high up, up to 100 km (62 mi) above the planet.[14] The clouds are very faint and can only be seen reflecting sunlight against the darkness of the night sky. In that respect, they look similar to the mesospheric clouds, also known as noctilucent clouds on Earth, which occur about 80 km (50 mi) above our planet. Of course, we’re all excited about finding liquid salty water on the surface of Mars. But any prospects of sending a rover or even humans to study these mini "rivers" might have to be dampened (sorry), owing to issues of contamination.The dark streaks known as recurring slope lineae (RSL) all but confirmed liquid water is present on the surface. Such regions, though, are likely to be designated "Special Regions" by the Committee on Space Research (COSPAR). These are places where only a sterile lander would be allowed to visit as per planetary protection rules, keeping them safe from Earth microbes, and potentially ruling out manned missions or a rover like Curiosity. In April, scientists reported in the same journal that (5)>> perchlorate salts, like the ones in the new study, were "widespread" on the surface of our planetary neighbour and humidity and temperature conditions just right for salty
(6)>>brines to exist 
Martian weather and soil conditions that NASA's Curiosity rover has measured, together with a type of salt found in Martian soil, could put liquid brine in the soil at night .Perchlorate identified in Martian soil by the Curiosity mission, and previously by NASA's Phoenix Mars Lander mission, has properties of absorbing water vapor from the atmosphere and lowering the freezing temperature of water. This has been proposed for years as a mechanism for possible existence of transient liquid brines at higher latitudes on modern Mars, despite the Red Planet's cold and dry conditions.New calculations were based on more than a full Mars year of temperature and humidity measurements by Curiosity. They indicate that conditions at the rover's near-equatorial location were favorable for small quantities of brine to form during some nights throughout the year, drying out again after sunrise. Conditions should be even more favorable at higher latitudes, where colder temperatures and more water vapor can result in higher relative humidity more often..Finding life in hidden reservoirs beneath the crimson sands of Mars would be revelatory. If the biochemistry of these microbes was the same as ours, we would suspect that rocks from long ago carried their ancestors to Earth. And that would mean .But if not, if we find life that’s unrelated to ours, then we’ll know of two worlds that have spawned biology – and will confront the unavoidable fact that the universe is teeming with living things.  I hope we're able to find some kind of life there. thatd be amazing and completely change the course of human history. of course there is life out there somewhere but to find it so close to home would be pretty cool

(1)>>  NASA’s press statement makes it seem that scientists have certain evidence of flowing water. They do not. What they have is chemical evidence that gives a strong suggestion of liquid water mixed with salts. More importantly, however, even if NASA was 100% certain that there is liquid water on Mars, it could not do anything about it. (2)>> In a paper published in the journal Nature Geoscience, scientists identified waterlogged molecules — salts of a type known as perchlorates — on the surface in readings from orbit. Although Mars had rivers, lakes and maybe even an ocean a few billion years ago, the modern moisture is modest — small patches of damp soil, not pools of
standing water. (3)>>Olympus Mons. is a very large shield volcano on the planet Mars. By one measure, it has a height of nearly 25 km (16 mi).[3] Olympus Mons stands almost three times as tall as Mount Everest's height above sea level. It is the youngest of the large volcanoes on Mars, having formed during Mars's Amazonian Period. It is currently the largest volcano discovered in the Solar System and had been known to astronomerssince the late 19th century as the albedo feature Nix Olympica (Latin for "Olympic Snow"). Its mountainous nature was suspected well before space probesconfirmed its identity as a mountain. The typical atmospheric pressure at the top of Olympus Mons is 72 pascal, about 12% of the average Martian surface pressure of 600 pascals. Even so, high-altitude orographic clouds frequently drift over the Olympus Mons summit, and airborne Martian dust is still present.[17] Although the average Martian surface atmospheric pressure is less than one percent of Earth's, the much lower gravity on Mars increases the atmosphere's scale height; in other words, Mars's atmosphere is expansive and does not drop off in density with height as sharply as Earth's.(4)>> The Martian atmosphere is composed mainly of carbon dioxide and has a mean surface pressure of about 600 pascals (Pa), much lower than the Earth's 101,000 Pa. One effect of this is that Mars' atmosphere can react much more quickly to a given energy input than that of Earth's atmosphere.[38] As a consequence, Mars is subject to strong thermal tides produced by solar heating rather than a gravitational influence. These tides can be significant, being up to 10% of the total atmospheric pressure (typically about 50 Pa). Earth's atmosphere experiences similar diurnal and semidiurnal tides but their effect is less noticeable because of Earth's much greater atmospheric mass.Although the temperature on Mars can reach above freezing (0 °C (273 K; 32 °F)), liquid water is unstable over much of the planet, as the atmospheric pressure is below water's triple point and water ice sublimes into water vapor. Exceptions to this are the low-lying areas of the planet, most notably in the Hellas Planitia impact basin, the largest such crater on Mars. It is so deep that the atmospheric pressure at the bottom reaches 1155 Pa, which is above the triple point, so if the temperature exceeded 0 °C liquid water could exist there. (5)>> perchlorate. Perchlorate is, among other things, dangerous to the human body, capable of disrupting the basic functioning of the metabolic system. Mars also appeals because of the evidence of water we’ve found there, especially in the soil. The trouble is that water isn’t the only substance we’ve discovered in the dirt of Mars. In 2009, scientists responsible for the Phoenix lander reported that they had discovered a statistically significant sample of perchlorate within the soil of the “polygon-patterned northern plains of the Vastitas Borealis.” If you’re left wondering what on Earth this might mean, you’re not alone. One of the investigators would later claim that his team had to look up the substance to find out what, exactly, they’d discovered. (6)>>brines. Brine is a solution of salt (usually sodium chloride) in water. In different contexts, brinemay refer to salt solutions ranging from about 3.5% (a typical concentration of seawater, or the lower end of solutions used for brining foods) up to about 26% (a typical saturated solution, depending on temperature).Salt deposits over much of Mars indicate that brine was abundant in Mars's past.[11][17] Salinity lowers the freezing point of water to sustain a liquid flow. Less saline water would freeze at the observed temperatures.[11] Thermal infrared data from the Thermal Emission Imaging System (THEMIS) on board the 2001 Mars Odyssey orbiter, have allowed the temperature conditions under which RSL form to be constrained. Liquid brine flows near the surface might explain this activity, but the exact source of the water and the mechanism behind its motion are not understood.[23][24] A hypothesis proposes that the needed water could originate in the seasonal oscillations of near-surface adsorbed water provided by the atmosphereperchlorates and other salts known to be present on the surface, are able to attract and hold water molecules from the surrounding environment (hygroscopic salts)

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