With the emergence of many new lunar projects (including the project Artemis subordinate NASAwith the aim of sending humans to moon Within a decade), the search for water on and under the Moon was gradually becoming a critical issue, both for the development of knowledge and for potential use projects for future missions. Manned, or even installed Moon base.

The terrestrial origin of lunar water?

Most of the water on the moon is attributed to comets Or asteroids that would deposit water during their collision with the moon during a period of time Big late bombardment – About 4 billion years ago, in a youth solar system, it is generally accepted that the planets of the inner solar system, as well as the Moon, were subjected to the effects of large asteroids. Some scientists are also beginning to see the solar wind as a possible source of water on the Moon: according to them, it can contain ions hydrogen andOxygen which can combine into molecules of water on the moon.

If none of these hypotheses is rejected, a team of scientists at New study The third hypothesis: What if the moon’s water came directly from the Earth?

In their model, it will be more accuratelyAtmosphere The upper part of our planet which could be a source of water for the Moon. In a natural and continuous way, the atmospheres of the planets are exposed to losses of Gas Atmosphere of outer space: This is calledair exhaust. This escape – which can have multiple causes – helped, among other things, to the emergence of life on Earth thanks to the escape of hydrogen, or also led to the disappearance of most of Mars’ atmosphere. Thus, the Earth’s atmosphere expels hydrogen and oxygen ions, which, according to scientists, can combine into water molecules on the Moon.

Magnetic field as a motor

But, according to the study, the flow of hydrogen and oxygen ions from the Earth’s atmosphere to the surface of the Moon is only possible thanks to the effects of Earth’s magnetic field : The latter is born magnetosphere, thus protecting the Earth from a large portion of charged solar particles. Scientists actually suggest that these ions are transported to the Moon as they pass through the tail of the magnetosphere – which is also the main source of Northern lights – , for a period of five days during the period of the lunar revolution.

But the process seems rather complicated: as it passes in the tail of the magnetosphere, the Moon causes turbulence there, some of which push the ions emitted from the Earth’s atmosphere back there; Thus the Moon is in the flow, and devoid of its protective magnetosphere, it accumulates ions that could once combine on the Moon to form permafrost The moon is at the poles.

Scientists support more than one argument: thanks to recent measurements made by various space agencies around the world, the presence of ions capable of forming water molecules during lunar transits was confirmed in this region of the magnetosphere.

In parallel, the team of scientists analyzed the gravity data collected by the probe lunar reconnaissance vehicle At the poles of the moon, to confirm the existence ofanomaly In certain places it indicates the presence of water (in the state hard where liquid) found in some porous rocks in the lunar polar regions: the latest estimates indicate that there are more than 3,500 km³ Water in the lunar polar regions of the only origin of terrestrial escape from the atmosphere!