A group of American scientists came to the conclusion that the most likely source of water trapped in the lunar soil, is the solar wind.
Speck of agglutinate - vitreous education in the lunar regolith. (The image of the authors.)

In recent years, observations with space probes and samples delivered to the Earth "Apollo", refuted the notion that the Moon is dry. For example, in 2009 the device LCROSS crashed into a permanently shadowed lunar crater, and in the material ejected by the clash, was found a surprising number of water ice. Water and related compounds were also found in the regolith layer of dust and stones covering the lunar surface.

But the origin of water on the moon's surface remains unclear. This is mainly the result of collisions with saturated water comets and other space debris or there are other sources? The theoretical model of stability lunar water, built in the late 1970s, talked about the fact that hydrogen ions (protons) from the solar wind can be combined with oxygen on the surface of the moon and to form water and related compounds hydroxyl group.

Yang Liu of the University of Tennessee (USA) and her colleagues have found a new confirmation of this hypothesis by analyzing samples brought by the "Apollo". Indeed, in the vitreous formations (the agglutinates)incurred in the lunar regolith in the fall, micrometeorites, found a significant number of hydroxyl.

Joint efforts infrared spectroscopy with the Fourier transform and secondary ion mass-spectrometry was able to detect the chemical form of hydrogen, as well as its quantity and isotopic composition. Thus found out that the source of hydroxyl steel solar wind protons, together with atoms of oxygen.

The regolith on the moon everywhere, and on the glass accounts for about half of the regolith. It turns out that the hydroxyl is widely distributed in the lunar material, though it is certainly not the ice or liquid water, which could easily take advantage of the inhabitants of future lunar bases.

Consequently, the ice in permanently shadowed polar craters of the moon, sometimes referred to as cold traps, can contain hydrogen atoms, ultimately derived from the solar wind. "It also means that water will probably exist on mercury and on asteroids, such as Vesta, or Eros, and then within the Solar system, said Ms. Liu. - All of them very different conditions on the surface, but it is possible to produce water."

The study is published in the journal Nature Geoscience.

Based on the materials from the University of Michigan.