The Russian-European mission “ExoMars – TGO” has received the first accurate information about the isotopic composition of water vapor in the Martian atmosphere.

Thanks to this, it will be possible to find out the history of the evaporation of Martian water into space. The study was published in this regard in the scientific journal Nature Astronomy.

And an article published by the magazine stated: “Our information indicates that in most cases, ordinary and heavy water molecules dissolve in the Martian atmosphere and evaporate into space at the time when the planet approaches the Sun as close as possible. This does not happen when Mars is at its farthest distance from the Sun. .

Recent studies have shown that ancient rivers, lakes and oceans of fresh water existed in the distant past on Mars. And it has the same amount of water, as is the case in the Earth’s Arctic Ocean. Scientists have not yet been able to know where this water disappeared and when it appeared on the surface of Mars.

This can be known after determining a ratio between deuterium and hydrogen in water molecules in the Martian atmosphere. This ratio may show how much water Mars has lost since its inception.

It is worth noting that deuterium escapes slowly as water molecules split from the planet’s atmosphere, increasing its share as the planet’s oceans evaporate into space. Scientists do not rule out that other factors may influence the rotation of deuterium, and that they can significantly distort assessments of the primary water reserves of Mars.

Based on the aforementioned principle, a team of planetary scientists managed by Juan Alday from Oxford University observed, during one Martian year, how the ratio of ordinary and heavy water vapors changed in different layers of the planet’s atmosphere. Based on this information and computer models of the Martian climate, astronomers determined how the shares of deuterium and hydrogen in the atmosphere fluctuated in different seasons, and also discovered when water molecules entered those regions of the atmosphere from where they could reach space.

Their information indicated that the proportion of deuterium in water molecules in the lower layers of the Martian atmosphere was about 4.9 times higher than in the Earth’s atmosphere. This confirms that Mars has lost huge amounts of moisture throughout its existence.

In addition, scientists have discovered that the rate at which water molecules disappear from the Martian atmosphere depends mainly on the location of the planet in orbit. When the planet was close to the sun, the rate reached its maximum value, and then began to drop to almost zero at other times of the year.

The researchers hope that additional observations of water vapor behavior using the instruments of the ExoMars mission will help learn new details about its escape from the Martian atmosphere. Which in turn provides an opportunity to learn about the appearance of the Red Planet in the distant past.