A team with China’s Chang’e 4 mission to the far side of the Moon has discovered a curious substance, which it describes (translated) as “gel-like.” They describe the material as dark greenish and glistening impact melt breccia, measuring 20 inches by six inches — signs of possible presence of glasses resulting from meteor impact melts or volcanic eruptions.
According to a report by Our Space, a Chinese-language science-outreach publication (and reported on by Space.com), the breccia — broken fragments of minerals cemented together — was formed by impact-generated welding, cementing and agglutinating of lunar regolith and breccia.
The paper also looks at the surrounding area, writes Space.com. The authors suggest that the lunar regolith consists of a mixture from multiple sources, including ejecta from the impact that created the nearby Finsen crater and possible contributions from Alder crater.