Although large dry valleys and oceans suggested that the water had long gone from the surface of Mars, the planet may not be the dusty world that captivated astronomers and inspired many novels and films science fiction. Contrary to what was believed, in its oxidized surface liquid water could flow.
During a press conference held yesterday by NASA, the team led by Lujendra Ojha, the Georgia Institute of Technology, presented what are considered the strongest evidence so far obtained for testing. “Our mission on Mars was” to trace the water “, we have compelling evidence that proves what we suspected for a long said John Grunsfeld, associate administrator for space agency norteamericana- This seems to confirm that water, even in the. as a brine flows today in the surface of Mars. “
Through images obtained with a spectrometer located on board the Mars Reconnaissance Orbiter (MRO), which orbits the planet for a decade The “chemical signature” that is characteristic of some hydrated salts mysterious dark streaks in the Martian soil that had been observed in 2011 was detected.
As these spots are noticed during the spring and summer, and disappear in winter as had been speculated that might be watercourses that freeze when temperatures drop
But the new measurements give greater credence to assumptions. Scientists believe that these veins could lead water by liquid salts that allow lower freezing temperatures; Mars, to -23 ° Celsius. Taking advantage of a similar effect here on Earth salt begins to routes to speed up the melting of snow and ice.
“With a spectrum analyzer, evidence of the presence of salts were found in the which could be dry riverbeds, and that suggests that there could have been water flowing astronomer explains the Uruguayan Gonzalo Tancredi, Vice President of the Division of Planetary Systems International Astronomical Union (IAU) -. They studied the darker areas and found signs of hydrated salts, more precisely, perchlorates, associated with reservoirs, which are deposited on the bottom of the bed. It would be the same process that occurs in the salt, as the water evaporates. “
To Romina Di Sisto, CONICET researcher and specialist in planetary sciences at the Faculty of Astronomical and Geophysical Sciences of the National University of La Plata, “salt is an indicator of the presence of recent water in that area, which are changing areas , which then changes to several passages of the probes are noticed. “
The study provided by these tests, published today in Nature Geoscience, the scientists also analyzed in great detail the images taken by a camera astonishingly MRO accurate, called HiRISE several formations and craters in areas below the Martian Ecuador. Ojha was first discovered these puzzling aspects while a student in 2010, but there are thousands of them documented in the Martian geography.
However, even if this discovery is confirmed, probably disappoint those who expect rivers and lakes to find the way to Earth. The pressure of the Martian atmosphere is so low that liquid water that may be on the surface immediately vaporizes. Current evidence points to traces, maybe water molecules.
The great mystery is where it comes For now, no one knows. The researchers speculate that perchlorates could be acting like a sponge and absorbs water from the atmosphere. Or it could come from underground reservoirs.
“The problem is that on Mars has detected water in the solid phase in the polar caps, and other areas also explains Tancredi- gas phase. But due to low pressure of the atmosphere, the range of conditions occurring water in liquid phase are very narrow. The relevance of liquid water is indispensable for the formation and development of life as we understood Him. Therefore ., the great goal of NASA missions to Mars was the detection of liquid water “
That would be good news: the finding again raises the possibility that there might be life on our planetary neighbor, but to maintain liquid water on Mars would have to be so salty that it would be extremely difficult.
“It is assumed that Mars has water inside systolic Di declares. What matters is whether there on the surface to see if there may be microorganisms, since there are some who could live in an environment of extreme salinity. “
Search for life on Mars, however, is more complicated than it seems. In fact, a joint review of the National Academy of Sciences of the United States and the European Science Foundation published last week just concluded that humanity is not prepared to do so. Human instruments could take terrestrial microbes and deposit them in the areas where it is intended to find extraterrestrial organisms.
As he writes Lee Billings in Scientific American, “pollution could sabotage the search for native Martians”.
So, before a spacecraft to visit another planet, it must be sterilized according to strict rules, which add not only development time, but also many millions of dollars to missions. “Even then says Billings, protocols may not be sufficiently tight as current techniques are unable to completely eliminate the germs of a spaceship, and nobody really knows the threshold conditions for bacteria to create self-sustaining colonies Mars or on Earth. “
Anyway, NASA plans a mission with a rover equal to Curiosity 2020 to make measurements, take radar equipment to detect underground aquifers and try to sample.
“As yet we can not solve the problem of complete sterilization of equipment ‘says Miguel San Martin, the Argentine engineer who was responsible for the decline precisely Curiosity, a mission to find organics on the planet rojo- is planned that the new rover take samples and put them in a jar for another mission after the find and put them in orbit. Then a third ship would go to look for them and bring them to Earth. It’s very complicated. Let planning a mission at a time. “
To Tancredi, this new finding” is an important step, but not a total confirmation. One would like to see the water flow. What happens is that this is an intermittent process that can take days or months. Now we have to monitor these areas in more detail. The presence of liquid water is important if you plan to install colonies on Mars. It is certainly a step further. Not definitive, but are strong evidence. “
” You have to take it cautiously -coincide Di systolic, because it is not direct evidence, but it seems consistent. These grooves can be threads of water with salt having lower freezing temperature. “
” We should not exaggerate too -opina San Martin. This is not a river. It is a very interesting situation, but does not change much what we do in the future. “
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