Mars is located at a relatively small distance from the Earth, while the conditions on the planet are relatively favorable for humans, in comparison with other planets of the solar system. At the moment, he is the most likely contender for the establishment of a human colony on it. Therefore, scientists from all over the world are watching him with interest. One of the mysteries of the planet, over which they puzzle – how and why the water disappeared. There is no doubt that one and a half billion years ago, she was here in large numbers. It is quite possible even that life existed here, but then a catastrophe occurred, which led Mars to its current state. Scientists’ interest in this planet is also caused by the fact that the processes that led to the “dehydration” of Mars could theoretically threaten the future and the Earth. An orbital probe and rovers help to find answers to these questions. And there are already some reasonable assumptions on this score.
Water on Mars “petrified”
According to scientists, almost the entire surface of the planet was covered with water, and the depth reached 1 km in some areas. However, at some point, the climate began to change dramatically. As a result, Mars became desolate and cold.
Earlier it was assumed that water, or rather hydrogen, which is its component, simply evaporated into space. This does not happen on Earth, for the reason that it has a magnetosphere. The latter does not allow the atmosphere to leave the side-altars of the planet. Mars does not have such a magnetosphere, which was the reason for the disappearance of water.
However, it later became clear that the rate at which hydrogen leaves Mars is rather low. Therefore, she would not have had time to evaporate during this time. If we assume that the rate of evaporation has always been uniform, then 33-90% of the original amount of water should have remained on Mars.
During the mission to Mars, scientists have found abundant evidence of water transformation. This is what California Institute professor Bethany Elman says. That is, in the process of modifying the bark, it absorbs liquid water and binds it into minerals.
According to Michael Meyer, head of NASA‘s Mars Science Program, most of the planet’s water has been trapped in minerals. Hydration, the process of imprisoning water in minerals, could touch huge volumes of liquid, up to a layer one kilometer deep.
Scientists have suggested that water on Mars disappeared between 4.1 and 3.7 billion years ago. This period of time is called the Noah period, during which the planet was heavily attacked by meteorites and asteroids. As a result, the available water is simply “petrified”. Computer modulation also confirmed this assumption using data from a rover, satellites, and even a Martian helicopter.
By the way, in 2018, information was received from the Mars Express interplanetary station that there is presumably a lake with liquid water in the South Pole region. Later, scientists began to agree that “water” is actually frozen clay .
Water on Mars disappeared as a result of sandstorms
Earlier in the journal Nature published an article in which an international team of scientists told how sandstorms on Mars probably caused the disappearance of water. As the scientific community suggests, the red planet lost its magnetic field about 4 billion years ago. As a result, as mentioned above, the water has become more vulnerable.
Scientists found out that sandstorms caused the disappearance of water by observing the red planet from the ExoMars satellite. Moreover, this process, which continues to this day, was noticed by chance, when, as a result of a strongly raised dust storm, communication with the rover was lost. As a result, the researchers had to observe it from orbit. They originally wanted to figure out how dust storms absorb light. However, they found that the water before the storm was at an altitude of 20-40 km.
The absorbing heat, and as a result, a well-heated sandstorm, in turn, heated the steam in the atmosphere, as a result of which it rose to an altitude of up to 80 km, where it split into hydrogen and oxygen. Thus, sandstorms could significantly accelerate the natural process of water disappearance in the past.
Mars never had water
According to a study by staff at the University of Arizona, large reservoirs of water on Mars originated from two different sources. That is, water on Mars has different origins. This fact led them to the conclusion that water on the planet appeared as a result of the fall of celestial bodies, and the red planet did not have its own ocean like that of the Earth.
The assumption of a different origin of water was confirmed by the study of meteorites NWA7034 and ALH84001 that broke away from Mars. These celestial bodies turned out to have the same isotope composition, but a different ratio of hydrogen isotopes with other rocks of the planet, which were studied by the Curiosity rover. One asteroid interacted with liquid about 1.5 billion years ago, and the second about 3.9 billion years ago. One of the types of rocks was similar in composition to bodies from distant parts of the solar system. The second was similar in composition to the rocks of the Earth.
Now, this assumption is looking for another scientific confirmation. As a result, it may turn out that each of the sounded versions takes place, that is, several factors could have influenced the disappearance of water on Mars at once.