Lunar surface water has received a lot of attention for its potential to exploit onsite resources for future lunar exploration missions and other space missions. Now, a research team led by Professor Sen Hu from the Institute of Geology and Geophysics (IGG) of the Chinese Academy of Sciences (CAS) has discovered that Chang’e-5 (CE5) contains impact glass beads in the lunar soil. some water.

Detailed investigations show that these glass balls are likely a new reservoir of water on the Moon, recording the dynamic inflow and outflow of water produced by the solar wind and acting as a buffer for the water cycle on the Moon’s surface. This work will be published in the journal today (March 27). Nature Geology.

Many lunar missions have confirmed the presence of structural water or water ice on the Moon. There is no doubt that most of the Moon’s surface contains water, although the amount is much smaller than on Earth.

Surface water on the Moon exhibits diurnal cycles and space loss, indicating that there must be a hydrated layer or reservoir deep within the lunar soil to support the retention, release, and regeneration of water on the lunar surface. However, previous studies of water reserves of small mineral grains, impact agglutinates, volcanic rocks, and pyroclastic glass beads in lunar soils have failed to explain the retention, release, and recharge of water on the Moon’s surface (i.e., water on the Moon’s surface). loop). Therefore, there must be an as-yet-unknown reservoir of water on the lunar soil capable of buffering the water cycle on the lunar surface.

Under Professor Sen Hu’s supervision, PhD student Huicun He suggested that impact glass beads, a ubiquitous component of amorphous soil on the Moon, are a potential candidate for investigating an unknown hydrate layer or reservoir in the lunar soil.

He systematically characterized the petrography, major element composition, water abundance, and hydrogen isotopic composition of pulsed glass beads rotated by the CE5 mission to identify and characterize the missing water reservoir on the lunar surface.

CE5 impact glass balls have a homogeneous chemical composition and a smooth open surface. They are characterized by a water content of about 2000 μg.g.^-one, with excess deuterium. The negative correlation between water abundance and hydrogen isotopic composition reflects the fact that the water in CE5 shock glass beads originates from solar winds.

The researchers also analyzed the amount of water across six sections in five glass spheres, showing hydration profiles of water produced by the solar wind. Some glass beads were clogged by a later degassing event. The impacted glass beads acted as a sponge to buffer the water cycle on the lunar surface. The researchers calculated that the amount of water the glass beads hit the lunar soil ranged from 3.0×10. ^11th kg to 2.7×10 ¹⁴ kilogram

“These findings show that impact glasses on the Moon’s surface and other airless bodies in the Solar System can store water produced by the solar wind and release it into space,” said Professor Hu.