The Solar Wind is Creating Water on the Surface of the Moon

Water on the Moon has become a hot topic. It was the first unambiguous discovery. Concentration levels were found to be high near the polar regions and in areas that were shrouded in shadow. Chang'e 5 didn't land in one of the permanently shadowed areas. soil samples were returned that were at a higher latitude than before A new study shows that the Sun's solar wind has an impact on the water in the soil.

Depending on the time of the lunar day and the latitude it is located at, the amount of water on the lunar surface is vastly different. The water content of the lunar soil can be higher or lower depending on the time of day. It appears that the Sun plays a significant role in the lunar cycle.

The type of hydrogen embedded into the lunar soil is controlled by that role. The charged hydrogen particles that make up the solar wind can interact with the top regolith layer on the moon. The sign that they leave behind is a large amount of hydrogen atoms.

A heavier form of hydrogen is called Deuterium. The extra mass of the neutron makes it less likely that it will be caught up in the force of the wind. Hydrogen and water that forms from the solar wind would not have the same chemistry as water that integrates deuterium.

That is what researchers at the Chinese Academy of Sciences found when they looked at some of the soil samples. There was a high concentration of hydrogen but a low concentration of deuterium. This result shows that the solar wind effect appears on the topmost layer of the regolith, as expected.

The water concentration in the Chang'e 5 sample was estimated to be around 46 parts per million, right around the time the landers touched down. The location of the study was important as the researchers tried to feed the concentration findings into a model that would show the outgassing from lunar water at other latitudes. There was less variability at the higher latitudes of Chang'e 5 than there was at the lower latitudes.

The model shows that even higher latitudes, reaching up toward the poles, would have more hydrogen. The belief is that the lunar poles are the most likely place to find large amounts of water on the lunar surface. The interest that the polar regions have in being the location of the first lunar research base feeds into that. The results from this study are an important step towards understanding this important feature of lunar hydrology.

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Solar wind-derived water is found in lunar soils.

There is a high amount of solar wind-derived water in the middle latitudes.

A collection of moon rocks was returned.

Some of the water from the Earth could have come from the moon.