Scientists have found out, where did the traces of recent water on Mars

© Photo : NASA/JPL/University of ArizonaСледы rivers of water in a crater on MarsScientists have found out, where did the traces of recent water on Mars© Photo : NASA/JPL/University of Arizona

. Mysterious fresh traces of water on the surface of Mars, found in recent years by NASA satellites, was the result of melting ice on the edges of large Martian craters after the fall of meteorites, according to a paper published in the journal Geophysical Research Letters.

«If these valleys arose as a result of groundwater seepage on Mars, traces of water would be present in the crater, but they are not there. Given where the ice reserves at the time, and the amount of melt water, which was to arise after the fall of red-hot rocks at the ice, we believe that the valley formed in this way,» says David Weiss (David Weiss) from brown University (USA).

In recent years scientists have found many hints that on the surface of Mars in ancient times there were rivers, lakes and entire oceans of water, which contained almost the same amount of liquid, like our Arctic ocean. On the other hand, some planetary scientists believe that even in the ancient era of Mars might be too cold for the continued existence of the oceans and its water could be in liquid state only during the time of the eruption of volcanoes or meteorites falling.

Recently, these ideas have shaken the planetary community found in the photos of some Martian craters near the equator of the red planet, such as Source and Jezero, and in the Northern polar latitudes, such as Leo, traces of water streams, which as recently as a few tens or hundreds of millions of years ago, I moved on the surface of Mars.

This discovery has led many scientists to wonder how liquid water could get to Mars and survive there long enough to form a network of shallow, but extensive channels on the slopes of these craters. Many scientists suggest that in the recent past, Mars could have a much more warm and soft climate, making an underground ice reserves in the most sunlit parts of the world could periodically be melted and to emerge after the fall of meteorites.

Weiss and his colleagues believe that it is not, after examining the structure of the valleys on the edges of the crater Lyot on the images that received the probe MRO in recent years. This crater is a gigantic basin with a diameter of 225 km and a depth of about seven kilometers, resulting from the fall of a large asteroid 3 or 1.6 billion years ago.

The edge of this crater is covered with a kind of «rivers» which flowed across the surface of Mars, according to estimates by Weiss and his colleagues, -1,8 about 1.2 billion years ago. Studying the structure of their riverbeds, scientists noticed an unusual thing – they were focused only on the Northern side of the crater Leo and never went inside his funnel, which was contrary to the idea of «dirt» the origin of rivers and valleys.

The answer to the mystery of how did these rivers, scientists have found, studying the circumstances of the birth of the crater Lyot. Team Weiss noticed that all of the channel and the valley of the «fresh» rivers in the surrounding area are where I had to drop molten fragments of soil and rock ejected by the collision of an asteroid with the surface of Mars.

According to calculations of geologists, their heat should be enough to melt significant reserves of ice beneath the surface of Mars and to obtain a sufficient amount of water is able to «pierce» the channels that exist on the Northern edge of the crater Lyot. Similarly, as scientists believe, could be formed and other traces of water on Mars in more southern regions, including those that today are considered to be traces of a more wet and warm era in the life of the red planet. This returns us to the idea that Mars was always cold, the scientists conclude.

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