About 4 billion years ago, almost the entire surface of Mars has been hidden under water. This conclusion was reached by scientists from France and the United States, finding hydrated silicates in the craters of the northern hemisphere of the planet.
One such site – Crater Lyot, located in the northern hemisphere, the red planet, contains a lot of water reservoirs. In the southern hemisphere of Mars betray the presence of water minerals (eg, phyllosilicates) were found even earlier. To investigate the opposite side of the planet more complicated, since traces of the liquid is buried under a thick layer of lava and sedimentary rocks.
The first evidence that the northern plains of Mars may be in hydrated silicates, handed Spectrometer OMEGA, mounted on board the apparatus of the European Space Agency Mars Express. In order to verify this information, researchers conducted additional observations using the CRISM spectrometer interplanetary station NASA Mars Reconnaissance Orbiter, which gives a higher resolution.
The authors examined 91 large craters with outcrops of ancient substance, and at least nine cases, they managed to find phyllosilicates. “Now we can say with confidence that more than four billion years ago, the whole surface of Mars has changed under the action of water,” – says study leader John Carter of the University of Paris-Sud 11.
Writing an accurate assessment of the conditions which prevail on ancient Mars, scientists, of course, can not yet, but certain assumptions they have. “The minerals rich in magnesium and iron and contain less aluminum, – tells a colleague, Jean-Pierre Bibring. – In addition, they are located next to olivine, which is easily modified by water. This implies that contact with the liquid only lasted a few tens or hundreds of millions of years. “