Why has water disappeared from Mars? It is a doubt to which numerous scientists and hypotheses work, and there are many in this regard. One of the last, and today the most interesting, is the one proposed by Geronimo Villaneuva, scientists of NASA who study water on the Red Planet together with some colleagues from the Russian Space Agency and the European Space Agency. According to the expert, the disappearance of the precious liquid from the planet could be attributed to the impetuous sand storms that surround Mars. There are two types: normal dust storms, which last a couple of days and are particularly extensive, so as to affect a surface comparable to that of the United States. And the global storms, which instead surround the entire planet and which, unlike the first ones, cannot be foreseen and can last for many months.
The last global dust storm, observed by the two rovers and six probes in orbit around Mars, was observed between the months of June and September of 2018. According to the expert, this type of storm would not merely lift the dust upwards but also water so that traces of water particles were detected by the ExoMars Trace Gas Orbiter even at 80 km height. Since it is a decidedly weaker atmosphere than the terrestrial one, these particles could have been separated from solar radiation and then ended up in space. In this way most of the water present on the Red Planet could have been lost as, as Villanueva pointed out, "when you bring water to higher parts of the atmosphere, it is wiped out much more easily".
No comments:
Post a Comment