Sunday, September 22, 2013

Life on Mars, when the end of the series? - Science and Life


It is extremely rare that NASA advertises “negative” , those who do not go in the direction of the dream. When the Hubble telescope detects the shadow of a planet in a distant star, the only question worth asking is “this exoplanet is habitable? “. When Cassini observed a magnificent geyser on Enceladus, inevitably, the press questioned the presence of possible life forms in the deep waters of the satellite of Saturn.
And Mars? Ah, Mars For fifteen years, Mars Pathfinder and Phoenix and Spirit and Opportunity , and finally Curiosity , all sought, or are seeking, by zooming in on this rock, pebble gratouillant such, evidence of past or present life on Mars. And from job to job, the probability that we find that life, in a living state, dare I write, or in a fossil state, seems to increase over the news. Each probe from Mars Pathfinder in 1997, brings grist Martian. “Discoveries” of river beds (actually known since 1976 …) “discovery” of water ice (known since 1947 …), the discovery of liquid water (it’s not safe, it is perhaps be brine or dry cast, we do not know yet), discovered clay, discovered methane, etc.. In short, a set of assumptions which ultimately results in 2013, this sensational announcement, the fruit of the labor of Curiosity for a year, “Mars was habitable in the past.” Space, so as exoplanets we discover each week throughout the galaxy, but inhabited?
That we do not know. The answer must come from Curiosity exploring the red planet for a year, feasting geologists, meteorologists, fans of alien landscapes. For the moment, therefore, measures Curiosity have shown that Mars was habitable.

But almost surprise (the same discovery was published last year), last week, Curiosity revealed … that there was not ultimately methane on Mars! It’s annoying, because researchers had to follow the trail of methane – assumed issued as on Earth, by living beings – to finally find the Martians, even when they track since almost 400 years … But the discovery of Curiosity arises another question: why if there is no methane on Mars, the Mars Express satellite has detected there in 2004? It is not yet known, or the data of the two robots are false, or the amount of methane has changed since ten years. This last hypothesis is unlikely, according to planetary scientists, who note that the sensitivity of Curiosity methane is much higher than that of probes in orbit, but rather to a failure of Mars Express we would go today. Still, the presence of methane obviously does not prove the existence of a form of life on Mars, methane is present everywhere in the universe, generated, for example, by volcanism. But do not smile , the absence of methane on Mars does not prove that life exists there … At the end of his statement, NASA was quick to point out that some micro terrestrial organisms do not emit methane … Still Martians, it must be admitted, are devious and irritating beings who are striving for four hundred years mystify Earth scientists who are desperate to get in touch with them …

At the end of the nineteenth century, the Martians dug canals on the surface of the Red Planet … You could see from afar. Missing channels after the astronomer Eugene Antoniadi has sounded the end of recess, in the early twentieth century, the red planet is covered with forests, grazing or strange animals. Then forests and large animals disappeared when the Mariner probes , alas, have shown for the first time Martian desert near … Never mind, chick lichens have replaced up ‘in 1976 and the Viking probes that have arisen on Mars and decreed that it was uninhabitable and uninhabited … The shock was so violent in the minds of men – basically science disenchanted the world – that they it shunned the red planet for more than a decade … Prior to 1976, twenty-three probes were gone tease Martians. Then no more! Then, in the late twentieth century, exobiologistes that needed work, have decreed that Viking had done wrong his own, and a new Martian armada was launched. The rest is history … habitability growing, residents more discreet … First of bacteria on the surface and in the subsurface ice. Today, without methane, new “habitats” must be devised in an emergency. Now the Martians are buried deep underground, where it can not identify, or they do not emit detectable signals, or both, which promises us a few centuries further research. Researchers concluded: Martians look with new ways

. In fact, this is what will make Americans together, Europeans and Russians in the coming years . Do not caricaturons. If this is the quest Martians causing some scientists, citizens and politicians – remember President Bill Clinton announced that they had perhaps found Martian life in a meteorite … – there is so much to discover the little cousin of the Earth, rightly emphasized the planetary. Atmosphere, for example. Probably dense, moist and thick during the formation of the planet, here 4.5 billion years, it is now dry and rarefied. Why? This is, among other things, the question that will attempt to answer the American probe Maven , which must take off in November. Insight , another American mission, with the participation of French laboratories, will look at the planet itself: complex, as evidenced by his spectacular geological formations, such as the giant canyon system of Valles Marineris, or the giant volcanoes of the Tharsis plateau, it has not yet delivered to the secrets of planetary evolution. Insight must leave Earth in March 2016 and ask the same year near the Curiosity probe in the Elysium region. New beautiful panoramas of the Martian desert
perspective … That said, the series of the search for life on Mars is not yet the beginnings of the early beginning of the end. Indeed, Europeans will continue to look for life on Mars with their program Exomars . In orbit, in 2016, a satellite attempt to detect the famous methane emissions of organisms living in the basement. Do not worry, it will not make it … Then, on the surface, in 2019, a mobile robot will dig a few tens of centimeters to find these very discreet and hypothetical organisms that exobiologistes now put in deep … As for astronauts they are in the starting block: arguing they would be far more effective than robots to find life on Mars – with good reason, since it would import billions of terrestrial bacteria and viruses – they are preparing to land on the red planet … one day …
Meanwhile, the rover Curiosity continues its journey in the area of ??scientific Aeolis Mons, looking for fossils or small animals hidden under rocks, you never know. Perhaps a little optimistic about its chances of success, NASA plans to send 2023 on March 1 “ Bi Curiosity “, equipped with more sensitive instruments. Comic repetition? Response – perhaps – in ten years …

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