Water on the Red Planet could have sloshed some 400 thousand years ago: the Chinese have changed the idea of when it disappeared
Water on Mars could have existed at a time when we – representatives of the genus Homo sapiens – already walked the earth. Chinese scientists from the Institute of Geology and Geophysics of the Chinese Academy of Sciences according to data obtained from the Zhurong rover (Zhurong), determined that deep oceans could splash on a neighboring planet between 1.4 million and 400 thousand years ago.
Photo: Chinese National Space Administration
Recall that «Zhuzhong» made a soft landing at Utopia Plain on May 14, 2021. By May 7, 2022, he had worked 349 sols (1 sol is equal to the duration of the average solar day on Mars, or «sol», that is, it is 24 hours 39 minutes and 35.244 seconds). During this time, the rover traveled about 2,000 kilometers and transmitted 940 GB of various scientific data to Earth. Then, in anticipation of the coming winter on Mars, he went into sleep mode. It was assumed that after wintering «Zhuzhong» will resume operation in December 2022, but the device has not yet come out of sleep mode.
The results, published by Chinese researchers, are based on earlier data obtained when the rover was still exploring the Utopia Plain.
Utopia Plain – a rounded lowland with a diameter of about 3300 km in the eastern part of the northern hemisphere of Mars. The plain is a former impact crater formed by an asteroid.
«Zhuzhong» examined the drawing of its dunes and «transferred» photographs of their thin cracked crusts to the researchers. They also contained accumulations of particles, very reminiscent of the salt sediment left after the evaporation of liquid water. An analysis of the dunes of Utopia showed that water could have been present on the planet between 1.4 million and 400 thousand years ago.
– The most interesting thing in this work, of course, – age of traces of water: between 1.4 million and 400 thousand years ago. It used to be thought that liquid water could have existed on Mars only billions of years ago.
– I note that it was not an ocean, not rivers: we know that at Martian low atmospheric pressure there could not have been any stable liquid water in those days on Mars. It was a brine, and a highly concentrated solution of salts, acids and other components unsuitable for life, which somehow seeped from the depths of Mars to the surface and immediately evaporated. From that water there were only stains of salt, like on shoes in winter. Naturally, no one could live in it.
The most important intrigue is that the Chinese discovered traces of salt water in the equatorial regions, where no one particularly expected the presence of water (water ice is concentrated mainly at the poles). However, we know that when the angle of inclination of the axis of rotation of Mars changes (this happens with different periods), the climate changes significantly, and water accumulates just in the region of the equator, in the so-called low latitudes.
– We know for sure that it exists in high latitudes, and there is a lot of it! In low latitudes, all available water can be bound in the form of hydrates (products of water addition to inorganic and organic substances. – ).